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1
Erdmann, Robert Gerald. "Image-Based Numerical Simulation of Stokes Flow in Porous Media." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/195724.
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Numerical models for the simulation of longitudinal and transverse Stokes flow in cylindrical periodic porous media are presented. The models, which are based on a finite-volume formulation in primitive variables, utilize digital image representations of the geometries to simulate, making them particularly well-suited for the rapid automated analysis of creeping flow in porous media with complex morphologies. Complete details of the model formulations are given, including extensive treatment of the pressure boundary conditions at the solid-liquid interface needed to guarantee convergence with all possible geometries. The convergence behavior of both models is tested, and the models are shown to be second-order accurate.The models are used to simulate flow over the whole range of volume fractions of liquid in several regular geometries. The longitudinal model is used to simulate flow in square arrays of circular and square ducts, and both models are used to simulate flow in square and hexagonal arrays of circular cylinders and square arrays of square cylinders rotated by varying amounts. For each of the geometries, accurate empirical expressions for the Darcy permeability as a function of volume fraction solid are presented. Where applicable, model predictions of permeability are compared to existing analytical results.Subsequently, the models are used to simulate Stokes flow in random domains over a wide range of fractions liquid. The sequential random packing algorithm is used to generate 1,000 random packings of circular cylinders at each of 14 fractions of liquid, and longitudinal and transverse flow simulations are performed for each geometry. Histograms and summary statistics are computed for the permeability for each fraction liquid, and empirical expressions for mean permeability as a function of fraction liquid are given. The autocorrelation structure of the geometry and of the fluid velocity is analyzed, and an analysis of the scaling of longitudinal permeability variance is presented. In transverse flow at high packing densities, it is found that lightning-like patterns emerge in the fluid velocity. It is also found that the details of flows in such geometries are strongly sensitive to the placement of individual solid obstacles.
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Arimoto, Shinichi. "Numerical method for coupled analysis of Navier-Stokes and Darcy flows." Kyoto University, 2018. http://hdl.handle.net/2433/232352.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第21151号
農博第2277号
新制||農||1059(附属図書館)
学位論文||H30||N5125(農学部図書室)
京都大学大学院農学研究科地域環境科学専攻
(主査)教授 村上 章, 教授 川島 茂人, 教授 藤原 正幸
学位規則第4条第1項該当
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Franks, Susan J. "Mathematical modelling of tumour growth and stability." Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366363.
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Hendrick, Angus Greer. "Effects of domain size on transverse permeability through random arrays of cylinders." Thesis, The University of Arizona, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3592730.
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Researchers using Darcy's law to model flow in porous media must satisfy the requirement for sufficient scale separation between the pore scale and the model scale. This requirement is analogous to that for any continuum model, where application is restricted to scales larger than the underlying discrete structure. In the case of Darcy's law when the model scale becomes too small, the measurement of the permeability—the material property required to close the relationship—becomes polluted by the boundary conditions, either physical or numerical. The requirements for adequate scale separation to obtain permeability measurements (also known as satisfying the conditions for a representative elementary volume, or REV, for permeability) have not been previously reported. Likewise, the behavior of Darcy models when applied at sub-REV length scales has not been reported.
Here, the results of Stokes simulations of transverse flow in 90,000 sequential random packings of monodisperse cylinders at a variety of liquid fractions and averaging-volume sizes show that approximately 200 cylinders must be present in an averaging volume before the effects of periodic boundary conditions on the Stokes simulations (the conventional choice for permeability measurements using Stokes flow) are no longer evident in the measured permeability. Direct comparisons between flow predictions from a two-dimensional, tensor-based Darcy model and a Stokes model for additional 10,000 domains show that the Darcy model is an unbiased predictor of the flow distribution in the system, even when the permeability is expected to contain boundary-condition artifacts. Though unbiased, the Darcy models do show considerable reduction in accuracy as the model scale shrinks toward the pore scale, with significant declines observed after the side length of a square averaging volume reaches 10 times the cylinder diameter. Finally, a novel approach for visualizing flows using the linear properties of the Stokes equations shows how the periodic boundary conditions affect the flow, and motivates the development of a generalized approach for obtaining permeability that does not require periodic boundary conditions. Modest improvements in the Darcy model relative to the actual Stokes flow result when the new approach is used to obtain permeability at small averaging volumes.
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Boussetouan, Imane. "Etudes théorique et numérique de quelques problèmes d'écoulements et de chaleur hyperbolique." Thesis, Saint-Etienne, 2012. http://www.theses.fr/2012STET4024.
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Ce travail de thèse a pour but d'étudier des écoulements non stationnaires de fluides incompressibles Newtoniens et non isothermes. Le problème est décrit par les lois de conservation de la masse, de la quantité de mouvement et de l'énergie. Nous nous intéressons au couplage entre le système de Navier-Stokes et l’équation de la chaleur hyperbolique (le résultat de la combinaison entre la loi de conservation d'énergie et la loi de Cattaneo). Cette dernière est une modification de la loi de Fourier utilisée habituellement, elle permet de surmonter « le paradoxe de la chaleur » et d'obtenir une description plus précise de la propagation de la chaleur. Le système couplé est un problème hyperbolique-parabolique dont la viscosité dépend de la température, alors que la capacité thermique et le terme de dissipation dépendent de la vitesse. Afin d’obtenir un résultat d'existence de solutions du problème couplé, nous démontrons d'abord l'existence et l'unicité de la solution du problème hyperbolique puis nous introduisons une discrétisation en temps et nous étudions la convergence des solutions approchées vers celles du problème original. Dans un deuxième temps nous étudions l'existence et l'unicité de la solution du système de Navier-Stokes muni des conditions aux limites de type Tresca puis de type Coulomb en dimension 2 et 3. Dans le chapitre 3, nous proposons une discrétisation en temps du problème d'écoulement dans le cas de la condition au limite de type Tresca et nous établissons la convergence des solutions approchées. Le dernier chapitre de ce mémoire est consacré à l'étude du problème couplé dans le cas de conditions aux limites de type Tresca. L'existence d'une solution est obtenue par un argument théorique de point fixe en dimension 2 et également par une méthode de discrétisation en temps qui conduit à résoudre sur chaque sous intervalle de temps un problème découplé pour la vitesse et la pression d'une part et la température d'autre partThe main objective of this thesis is to study nonstationary flows of incompressible Newtonian and non isothermal fluids. The problem is described by the laws of conservation of mass, momentum and energy. We consider the coupling between the Navier-Stokes system and the hyperbolic heat equation (the result of combination between the law of conservation of energy and the Cattaneo’s law). This one is a modification of the commonly used Fourier's law, it overcomes "the heat paradox" and gives a more accurate description of heat propagation. The coupled system is an hyperbolic-parabolic problem where the viscosity depends on the temperature but the thermal capacity and the dissipative term depend on the velocity. To obtain an existence result for the coupled system, we first prove the existence and uniqueness of the solution of the hyperbolic problem then we introduce a time discretization and we study the convergence of the approximate solutions to those of the original problem. In the second chapter, we study the existence and uniqueness of the solution of Navier-Stokes system with Tresca or Coulomb boundary conditions in dimension 2 and 3. In the third chapter, we propose a time discretization of the flow problem in the case of Tresca boundary conditions and we establish the convergence of the approximate solutions. The last chapter is devoted to the study of the coupled problem in the case of Tresca free boundary conditions. The existence of a solution is obtained by a theoretical argument (fixed-point theorem) in dimension 2 and also by a method of time discretization leading, on each time subinterval, to a decoupled problem for the velocity and pressure of a hand and the temperature of the other hand
6
Polavieja, Gonzalo Garcia de. "Geometric phase and angle for noncyclic adiabatic change, revivals and measures of quantal instability." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325986.
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Debbiche, Hanene. "Sur des problèmes de lubrification stationnaires et instationnaires non isothermes." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSES027/document.
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L’objectif de ce travail de thèse est d’étudier quelques problèmes elliptiques et paraboliques d’écoulement de fluides non Newtoniens incompressibles et non isothermes gouvernés par l’équation aux dérivées partielles de Stokes avec la condition de Tresca sur une partie du bord quand la viscosité dépend à la fois de la température, de la vitesse et du module du tenseur des taux de déformations. Dans le premier chapitre, on a fait une introduction générale. Dans le deuxième chapitre, nous nous intéressons au couplage entre le système de Stokes et l’équation de la chaleur en régime stationnaire. On montre l’existence de la solution de l’inéquation variationnelle décrivant le système de Stokes pour une température donnée quand la viscosité dépend à la fois de la température, de la vitesse et du module du tenseur des taux de déformations en utilisant la méthode de monotonie pour la vitesse et le théorème de De Rham pour la pression. Dans un deuxième temps, on étudie l’existence et l’unicité de la température solution de l’équation de la chaleur avec un terme L1(Ω) au second membre quand la viscosité dépend à la fois de la température, de la vitesse et du module du tenseur des taux de déformations. On montre ensuite l’existence de la solution du problème variationnel couplé avec la viscosité dépend de la température et du module du tenseur des taux de déformations, en utilisant le théorème de point fixe de Schauder. Dans le troisième et le quatrième chapitre, on traite l’existence et l’unicité de la solution du système de Stokes en régime instationnaire quand la viscosité dépend de la température et du module du tenseur des taux de déformations dans les cas p = 2, p > 2 et 6 5 < p < 2 en utilisant la notion des semi-groupes et la méthode de monotonie pour la vitesse et le théorème de De Rham pour la pression. Par contre, lorsque la viscosité dépend de plus de la vitesse on obtient seulement l’existence par le théorème de point fixe de SchauderThe objective of this thesis is to study some elliptic and parabolic problems of the non-Newtonian flow of an incompressible and non isothermal fluid governed by partial differential equation of Stokes with Tresca’s condition on a part of the boundary when the fluid viscosity depends on temperature and also on the modulus of strain rate tensor and the velocity of the fluid. In the first chapter, we did a general introduction. In the second chapter, we consider the coupling between the Stokes systemand the heat equation in steady state. We prove the existence of a solution of the variational inequality describing the Stokes system when the fluid viscosity depends on temperature and also on the modulus of strain rate tensor and the velocity of the fluid of a given temperature by using the monotony methods for the velocity and De Rham’s theorem for the pressure. We study the existence and uniqueness of the temperature solution of the heat equation with L1 (Ω) term to the second member when the fluid viscosity depends on temperature and also on the modulus of strain rate tensor and the velocity of the fluid. We show the existence of a solution of the coupled variational problem when the fluid viscosity depends on temperature and also on the modulus of strain rate tensor by using Schauder fixed point theorem. In the third and the fourth chapter, we treate the existence and uniqueness of a solution of the Stokes system in unsteady state when the fluid viscosity depends only on temperature and on the modulus of strain rate tensor in the cases p = 2, p > 2 and 6 5 < p < 2 by using the notion of semigroup and monotony methods for the velocity and De Rham’s theorem for the pressure. However, when the fluid viscosity depends also on the velocity of the fluid we obtain only the existence by Schauder fixed point theorem
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Itami, Masato. "Non-equilibrium Statistical Theory for Singular Fluid Stresses." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215285.
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Sita, Ram Rao K. V. "Wall Effects In Packed Beds." Thesis, Indian Institute of Science, 1994. http://hdl.handle.net/2005/126.
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Packed beds find extensive application in a wide variety of industries. The objective of the present work is to analyze and evaluate the effects of the wall on structural characteristics, hydrodynamics and heat transfer in packed beds of spheres. As a first attempt, spheres of uniform size are considered.
The cylindrical wall of the bed confines the location of the particles thus leading to significant radial variations in void fraction and specific lateral surface area. The two characteristics at any given radial position r* are estimated by defining a concentric cylindrical channel (CCC) of an arbitrary thickness such that its boundaries are equidistant from the cylindrical surface passing through r* and accounting for the solid volumes or lateral surface areas of the segments of spheres (cap, slice, rod and annular ring) contained in the CCC and with centers lying within a distance of a particle radius from r*.The curved boundaries of the sphere segments are rigorously accounted for. The low aspect ratio beds (aspect ratio less than or equal to 2) show three distinct types of behavior. In beds of aspect ratio 2, the void fraction starts from a value of unity at the wall and decreases to a minimum and then increases to unity at the center of the bed. In beds with aspect ratio between l\/¯3/2, there is a continuous decrease in void fraction from unity at the wall to a fairly low value towards the axis and then a slight increase followed by another decrease. The profiles for aspect ratio less than l\/¯3/2 show a continuous decrease from a value of unity at the wall to zero towards the axis. In contrast, beds of high aspect ratio show heavily damped oscillations in the void fraction up to about five particle diameters from the wall and then a constant value. The lateral surface area variations in low aspect ratio beds show a steep fall from a very high value near the wall, and in high aspect ratio beds an oscillatory nature, though not as strong as in the corresponding void fraction profiles.
The distribution of flow in packed beds for steady flow of an incompressible Newtonian fluid under isothermal conditions is modeled by using Ergun equation with Brinkman-type correction to account for the viscous effects in the region close to the wall. The confining effect of the wall is incorporated through the radial variations in void fraction and specific lateral surface area. The hydraulic radius in the region next to the wall is modified to take into account the resistance of the wall surface to flow. The resulting model equations with appropriate boundary conditions are solved numerically by collocation technique. The influence of aspect ratio in the range 1.25 to 20.3 and Reynolds number from 0.1 to 1000, the two most important factors affecting the flow behavior, is evaluated. The velocity profiles show a peak in the region close to the wall thus indicating severe channeling effect in this region. The magnitude and location of the peak depend on aspect ratio and Reynolds number. The model predictions agree remarkably with reported experimental data on velocity profiles in a bed of aspect ratio 10.7, and on the effect of Reynolds number on friction factors in beds of low aspect ratio.
The radial variations in void fraction, velocity and effective thermal conductivity are incorporated in the two-dimensional pseudo-homogeneous steady-state model to analyze the wall effects on heat transfer in packed beds. Both constant wall temperature and constant wall flux boundary conditions are adopted. The equations are solved numerically using finite difference technique. The radial temperature profiles are seen to be fairly uniform in beds of low aspect ratio thus showing that the often made assumption of complete radial thermal mixing in low aspect ratio beds is valid. Beds of high aspect ratio show strong radial gradients. For constant heat flux condition the slope of the temperature profile remains constant after a small distance from the Inlet thus leading to thermally fully-developed flow. For this condition the heat transfer equations are solved analytically to obtain expressions for Nusselt number and the radial temperature profiles. There is a significant difference in the temperature profiles evaluated in the presence and absence of wall effects. Good agreement is found between the Nusselt numbers obtained from the model and reported experimental data.
10
Marusic-Paloka, Eduard. "Modélisation par homogénéisation des écoulements en milieux poreux fissurés." Saint-Etienne, 1995. http://www.theses.fr/1995STET4008.
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Dans cette thèse nous présentons plusieurs résultats qui concernent l'homogénéisation appliquée à la modélisation des milieux poreux. Elle est composée de quatre chapitres indépendants. Dans les premier et deuxième chapitres nous étudions le comportement effectif des solutions de l'équation de Laplace et du système de Stokes dans un milieu poreux, contenant une fissure mince. Suivant la relation entre la taille caractéristique des pores et l'épaisseur de la fissure nous trouvons trois modèles différents. Le troisième chapitre présente un résultat qui concerne les estimations d'erreur pour les correcteurs dans l'homogénéisation du système de Stokes et de Navier-Stokes, pour un milieu poreux. Dans le dernier chapitre nous étudions les effets inertiels pour un écoulement visqueux, rapide dans une couche ondulée. Nous trouvons une loi globale non linéaire
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Halfhill, Andrew James. "A Report on Internships at Donovan Law and Federated Department Stores, Inc." Miami University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=miami1112033472.
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Gastou-Chassaing, Marie-Isabelle. "Chaos lagrangien entre ellipses confocales : étude théorique, numérique et expérimentale." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL103N.
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Un fluide visqueux newtonien est introduit entre deux ellipses confocables dont les parois interne et externe peuvent être déplacées le long de leur circonférence. Une solution analytique en coordonnées elliptiques a été récemment obtenue à partir des hypothèses du régime de Stokes. Les sections de Poincaré, les points périodiques de l'écoulement et l'évolution d'une tache de traceur, montrent qu'un régime de chaos lagrangien avec de grandes surfaces potentielles de mélange peut se développer dans cette géométrie qui est également un échangeur de chaleur efficace. Le dispositif expérimental a été construit et testé. Les résultats des études théoriques et numériques ont été confrontés avec succès aux résultats expérimentaux par les méthodes suivantes: lignes de courant, déformation de taches de traceur fluorescent, sensibilité aux conditions initiales, test de nombreux profils de vitesses des parois, étude d'écoulements asymptotiques. L’analogie entre les résultats dérives de la géométrie à ellipses concentriques et de la géométrie à cercles excentrés donne des règles générales sur le comportement des mélangeurs bi-dimensionnels annulaires: importance de l'origine relative de l'énergie transférée au fluide, efficacité de l'addition de petits effets inertiels. Des applications directes importantes de cette recherche sont proposées: développement d'une méthode simple d'optimisation de mélangeurs par un choix judicieux de profils de vitesse élémentaires ; développement de nouveaux outils (sections de Poincaré et étude entropique) pour optimiser la conception de nouveaux mélangeurs
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McNeil, C. Y. "Efficient upwind algorithms for solution of the Euler and Navier-stokes equations." Thesis, Cranfield University, 1995. http://hdl.handle.net/1826/4147.
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An efficient three-dimensionasl tructured solver for the Euler and
Navier-Stokese quations is developed based on a finite volume upwind algorithm
using Roe fluxes. Multigrid and optimal smoothing multi-stage time stepping accelerate convergence. The accuracy of the new solver is demonstrated for inviscid
flows in the range 0.675 :5M :5 25. A comparative grid convergence study for
transonic turbulent flow about a wing is conducted with the present solver and
a scalar dissipation central difference industrial design solver. The upwind solver
demonstrates faster grid convergence than the central scheme, producing more
consistent estimates of lift, drag and boundary layer parameters. In transonic
viscous computations, the upwind scheme with convergence acceleration is over
20 times more efficient than without it. The ability of the upwind solver to compute
viscous flows of comparable accuracy to scalar dissipation central schemes
on grids of one-quarter the density make it a more accurate, cost effective alternative.
In addition, an original convergencea cceleration method termed shock
acceleration is proposed. The method is designed to reduce the errors caused by
the shock wave singularity M -+ 1, based on a localized treatment of discontinuities.
Acceleration models are formulated for an inhomogeneous PDE in one
variable. Results for the Roe and Engquist-Osher schemes demonstrate an order
of magnitude improvement in the rate of convergence. One of the acceleration
models is extended to the quasi one-dimensiona Euler equations for duct flow.
Results for this case d monstrate a marked increase in convergence with negligible
loss in accuracy when the acceleration procedure is applied after the shock
has settled in its final cell. Typically, the method saves up to 60% in computational
expense. Significantly, the performance gain is entirely at the expense of
the error modes associated with discrete shock structure. In view of the success
achieved, further development of the method is proposed.
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Stoots-Fonberg, Chasity Anne. "Misguided Instructions: Do Jurors Accurately Understand the Law in Death Penalty Trials?" [Johnson City, Tenn. : East Tennessee State University], 2003. http://etd-submit.etsu.edu/etd/theses/available/etd-0220103-232646/unrestricted/Stoots-FondbergC040303f.pdf.
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Thesis (M.A.)--East Tennessee State University, 2003.Title from electronic submission form. ETSU ETD database URN: etd-0220103-232646. Includes bibliographical references. Also available via Internet at the UMI web site.
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Letarte, Lyne. "Régime juridique des provisions de bord en droit aérien = Legal status of aircraft stores." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63834.
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Cooke, LaNina N. "Religious establishments, public housing, and liquor stores| Their prediction of juvenile system behavior." Thesis, City University of New York, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3561209.
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The following dissertation examines the role of ecological structures in juvenile justice systems, specifically during risk assessment, prosecution, and sanctioning. This analysis of system behavior considers religious establishments, public housing, and liquor stores as the ecological indicators and views them as stigmatizing. Quantitatively, the following examination sought to (a) determine associations between social ecology and risk assessments, prosecutions, and residential sanctioning, and to (b) determine if juvenile probation officers and judges are more stringent and judgmental toward delinquents from neighborhoods that have greater concentrations of religious establishments, public housing, and liquor stores. All adjudicated juvenile delinquents whose cases have been decided by the Florida Department of Juvenile Justice in calendar years 2006, 2007 and 2008 were included in the analysis. Secondary data from the Florida Department of Juvenile Justice, the Division of Alcoholic Beverages and Tobacco Bureau of Licenses, the United States Department of Housing and Urban Development, American Church List and the United States Census were used to address the research questions.
The databases were used to support the researcher's overall tenet that certain areas are perceived as disorganized, which leads to stricter expressions of risk assessment, prosecutions, and residential sanctions. It is hypothesized that, (1) risk assessment levels are higher in areas with more religious establishments, public housing, and liquor stores; (2) zip codes with more prosecutions will consequently be those with more of the stigmatized ecological structures; and (3) an increase in religious establishments, public housing, and liquor stores will generate an increase in residential sanctions.
It was expected that the relationship between the independent and dependent variables would be significant, over and beyond demographic and legal factors. In the analysis, area demographics of population density; and juvenile demographics of age, race, ethnicity, and gender, along with current and prior legal history, were controlled for to determine the predictive value of the independent variables of religious establishments, public housing, and liquor stores on the dependent variables of risk assessment, prosecutions, and residential sanctions. Prior to statistical analysis, the data was merged and aggregated by zip code to reflect area composition, resulting in a dataset of 298 zip codes and 21 variables. To examine these relationships, analyses were done on a bi-variate and multi-variate level. Multi-variate analysis was performed using hierarchical regression. Three models were designed, considering demographics, and then adding legal variables, followed by ecological structures, to make the complete model.
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Maidana, Manuel Augusto. "Desarrollo de un modelo numérico 3D en elementos finitos para las ecuaciones de Navier-Stokes : aplicaciones oceanográficas." Doctoral thesis, Universitat Politècnica de Catalunya, 2007. http://hdl.handle.net/10803/457520.
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En esta tesis se ha desarrollado y validado un modelo tridimensional de circulación costera en elementos finitos capaz de simular una región limitada del océano. La escala de longitud de las aplicaciones pueden ser del orden del ancho de la plataforma continental o menores y la escala de tiempo entre el período de las ondas de las mareas y de las ondas debidas al viento.
La formulación del modelo, denominado HELIKE, está basada en las tres componentes de la ecuación de Navier-Stokes (no-hidrostáticas) y tiene en cuenta las dos componentes de la aceleración de Coriolis, (componentes normal y tangencial a la superficie terrestre), gradientes de densidad, turbulencia (valores constantes o modelos de turbulencia como Smagorinsky, Munk-Anderson o Pacanowski-Philander), fricción con fondo, tensión de viento y superficie libre. Pudiéndose también utilizar el modelo en fondos con batimetrías irregulares (fondo no-horizontal).
Los modelos tridimensionales no-hidrostáticos como el desarrollado en esta tesis están bien planteados para dominios con contorno abierto. Esto es muy importante en el modelado de mesoescala donde el modelado de la pequeña, pero relevante, velocidad vertical es importante y los contornos abiertos son inevitables. La formulación no-hidrostática tiene fundamentalmente importancia cuando la escala horizontal del movimiento se hace comparable con su escala vertical y no se pueda despreciar la velocidad vertical como por ejemplo, se da el caso en la circulación sobre fondos abruptos, convección en el océano abierto, etc.
El uso combinado de una discretización espacial por el método de los elementos finitos y el uso de mallas no-estructuradas proveen al modelo una gran flexibilidad para adaptarse a la complicada geometría de la línea de costa y del fondo marino. Además de la posibilidad de realizar refinamientos de la malla sobre áreas de mayor interés y aplicar las condiciones de contorno apropiadas para cada caso.In this thesis finite element model was developed, named HELIKE, for the numerical simulation of the three-dimensional, turbulent, non-hydrostatic, free-surface flows like those arising in the study of the motion of water in coastal regions. The kinematic free-surface equation is used to compute the surface elevation, without resorting to vertical averages. The model developed here incorporates surface wind stress, bottom friction, Coriolis acceleration, the baroclinic term to take account the density gradients, and it is applicable to irregular bottom topographies. A pressure stabilization technique is employed to stabilize the finite element solution. Numerical results confirm the accuracy, robustness and applicability of the proposed method.
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Bernales, chavez Braulio. "Modélisation de l'hydrodynamique et des transferts dans les procédés de filtration membranaire." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4779/document.
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L'accumulation du soluté à la surface d'une membrane entraîne le phénomène de polarisation de concentration. Ceci est un problème qui affecte tous les systèmes de filtration membranaire car il a pour effet une augmentation de la pression osmotique et par conséquence une réduction substantielle du flux de perméat. Afin de comprendre ce phénomène, nous avons d'abord mené une étude analytique de la filtration tangentielle en solvant pur prenant en compte de l'influence de la pression motrice locale sur le taux de perméation. Lors de cette étude, des solutions analytiques qui augmentent en précision avec l'ordre développé ont ete dérivées. Ensuite nous avons développé une approche analytique qui couple l'hydrodynamique aux transferts de matière pour le cas d'un système de filtration qui opère sous haute pression avec un taux de récupération faible. Dans le but d'intégrer à la fois la dépendance de la pression transmembranaire locale sur le flux de perméat et l'influence de la polarisation de concentration à travers leurs effets osmotiques sur la pression effective, nous avons développé un modèle numérique qui résout l'équation de conservation du soluté couplée aux équations de Navier-Stokes en régime stationnaire dans l'approximation de Prandtl. Nous avons validé cette approche grâce aux solutions analytiques précédemment dérivées. Ensuite, nous avons testé l'influence des principaux paramètres de fonctionnement sur la performance du système et comparé nos résultats avec ceux d'autres modèles numériques. Finalement, la pertinence du modèle a été quantitativement vérifiée grâce à des données tirées des expériences bien documentées en osmose inverseConcentration polarization of solute at the membrane surface, because of osmotic pressure effects, is an important phenomenon that can cause substantial reductions in permeation. To understand these phenomena: we first analyze the filtration process for a pure solvent, imposing the influence of the driving pressure on permeation at the membrane. We obtain accurate analytical solutions for the flow fields. We then derive an analytical solution that coupled hydrodynamics to mass transfer for filtration systems working in a situation of High Pressure and Low Recovery. Second, we develop a numerical model that incorporates both physical aspects: the dependency of pressure on permeation and the influence of concentration polarization and their related osmotic effects in the effective pressure at the membrane. For that, the numerical approach solves the solute conservation equation coupled with the Navier-Stokes equations under the steady Prandtl approximation. The solution of the system is performed using a finite difference method of order 2. The validity of this approach is successfully demonstrated with the previous analytical solutions for hydrodynamics, as well as for the coupling with mass transfer. We then test the influence of the main operating parameters (inlet concentration, axial flow rate, operating pressure and membrane permeability) on the performance of the filtration system and compare the results with other numerical models that takes into account concentration polarization phenomenon. Finally, the validity of this model is quantitatively well-proved when using the reported data resulting from reverse osmosis experiments
19
Soltanzadeh, Hamed [Verfasser], and Eberhard [Gutachter] Schlücker. "The extended Navier-Stokes equations and their application to the lay-out of diffusion dryers / Hamed Soltanzadeh ; Gutachter: Eberhard Schlücker." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2018. http://d-nb.info/1154308677/34.
Full text
20
Worthy, Jude. "Large eddy simulation of buoyant plumes." Thesis, Cranfield University, 2003. http://hdl.handle.net/1826/92.
Full textAbstract:
A 3d parallel CFD code is written to investigate the characteristics of and differences
between Large Eddy Simulation (LES) models in the context of simulating a thermal
buoyant plume. An efficient multigrid scheme is incorporated to solve the Poisson
equation, resulting from the fractional step, projection method used to solve the Low
Mach Number (LMN) Navier-Stokes equations.
A wide range of LES models are implemented, including a variety of eddy models,
structure models, mixed models and dynamic models, for both the momentum stresses
and the temperature fluxes. Generalised gradient flux models are adapted from their
RANS counterparts, and also tested.
A number of characteristics are observed in the LES models relating to the thermal
plume simulation in particular and turbulence in general. Effects on transition,
dissipation, backscatter, equation balances, intermittency and energy spectra are all
considered, as are the impact of the governing equations, the discretisation scheme,
and the effect of grid coarsening. Also characteristics to particular models are
considered, including the subgrid kinetic energy for the one-equation models, and
constant histories for dynamic models.
The argument that choice of LES model is unimportant is shown to be incorrect as a
general statement, and a recommendation for when the models are best used is given.
21
Latige, Manuel. "Simulation numérique de l'ablation liquide." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2013. http://tel.archives-ouvertes.fr/tel-00858600.
Full textAbstract:
Lors de la phase de rentrée atmosphérique d'une sonde spatiale, la paroi du corps est le siège de phénomènes physico-chimiques complexes. Nous nous intéressons dans cette thèse au cas où le matériau solide de l'objet de vol comporte plusieurs constituants s'ablatant de façon différentielle. En particulier, l'un de ces constituants subit un changement de phase donnant lieu à l'apparition d'une phase liquide. Nous sommes en présence de trois phases : solide, liquide et gaz. Les travaux effectués dans cette thèse correspondent au développement de méthodes numériques en 2D capables de modéliser les différentes interfaces en présence ainsi que l'évolution des fluides ou des matériaux séparés par celle-ci. L'enjeu principal de la thèse est de proposer des méthodes et des algorithmes de couplage pour l'écoulement diphasique, la thermique multimatériaux et les changements de phase (fusion et sublimation)
22
Sauvé-Schenk, Katrine. "The Influence of a Low-Income and Linguistic Minority Context on Post-Stroke Participation." Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/37114.
Full textAbstract:
Following a stroke, the majority of survivors experience challenges returning to participation, also known as “involvement in life situations” in the International Classification of Functioning, Health, and Disability. Contextual factors, such as low income and linguistic minority status, have been shown to have an impact on participation post stroke; however, the process by which this occurs is poorly understood. The aim of this research was to increase our understanding of how low income and official minority language status influence the experience of return to participation following a stroke.
A qualitative multiple case study approach was used with eight francophone stroke survivors living in a low-income situation in eastern Ontario (Canada). Data was collected from several sources: semi-structured interviews with the stroke survivors and with their care partners, participant observations, four measures, and chart reviews. Data was categorised, and patterns that furthered understanding of the experience of return to participation were identified during intra and cross-case analyses.
The stroke survivors were all able to access healthcare and social services in both official languages, and the findings suggest that official language minority status had limited influence on the experience of return to participation. Low income, however, influenced precursors to participation by limiting the stroke survivors’ ability to afford housing, goods (e.g., medication, equipment), and services (e.g., transportation, private therapy).
Certain personal and environmental factors modulated the experience of return to participation – specifically, age, knowledge of the healthcare and social service systems, support of family and friends, the built environment, and health literacy. The healthcare and social policies of the macro environment, which regulates the healthcare and social services, had a critical influence on the experience of return to participation for these stroke survivors, irrespective of their individual situations, unless wealth or financial support was available.
23
Nadukandi, Prashanth. "Stabilized finite element methods for convection-diffusion-reaction, helmholtz and stokes problems." Doctoral thesis, Universitat Politècnica de Catalunya, 2011. http://hdl.handle.net/10803/109155.
Full textAbstract:
We present three new stabilized finite element (FE) based Petrov-Galerkin methods for the convection-diffusionreaction
(CDR), the Helmholtz and the Stokes problems, respectively. The work embarks upon a priori analysis of a
consistency recovery procedure for some stabilization methods belonging to the Petrov- Galerkin framework. It was
ound that the use of some standard practices (e.g. M-Matrices theory) for the design of essentially non-oscillatory
numerical methods is not appropriate when consistency recovery methods are employed. Hence, with respect to
convective stabilization, such recovery methods are not preferred. Next, we present the design of a high-resolution
Petrov-Galerkin (HRPG) method for the CDR problem. The structure of the method in 1 D is identical to the consistent
approximate upwind (CAU) Petrov-Galerkin method [doi: 10.1016/0045-7825(88)90108-9] except for the definitions of
he stabilization parameters. Such a structure may also be attained via the Finite Calculus (FIC) procedure [doi:
10.1 016/S0045-7825(97)00119-9] by an appropriate definition of the characteristic length. The prefix high-resolution is
used here in the sense popularized by Harten, i.e. second order accuracy for smooth/regular regimes and good
shock-capturing in non-regular re9jmes. The design procedure in 1 D embarks on the problem of circumventing the
Gibbs phenomenon observed in L projections. Next, we study the conditions on the stabilization parameters to
ircumvent the global oscillations due to the convective term. A conjuncture of the two results is made to deal with the
problem at hand that is usually plagued by Gibbs, global and dispersive oscillations in the numerical solution. A multi
dimensional extension of the HRPG method using multi-linear block finite elements is also presented.
Next, we propose a higher-order compact scheme (involving two parameters) on structured meshes for the Helmholtz
equation. Making the parameters equal, we recover the alpha-interpolation of the Galerkin finite element method
(FEM) and the classical central finite difference method. In 1 D this scheme is identical to the alpha-interpolation
method [doi: 10.1 016/0771 -050X(82)90002-X] and in 2D choosing the value 0.5 for both the parameters, we recover
he generalized fourth-order compact Pade approximation [doi: 10.1 006/jcph.1995.1134, doi: 10.1016/S0045-
7825(98)00023-1] (therein using the parameter V = 2). We follow [doi: 10.1 016/0045-7825(95)00890-X] for the
analysis of this scheme and its performance on square meshes is compared with that of the quasi-stabilized FEM [doi:
10.1016/0045-7825(95)00890-X]. Generic expressions for the parameters are given that guarantees a dispersion
accuracy of sixth-order should the parameters be distinct and fourth-order should they be equal. In the later case, an
expression for the parameter is given that minimizes the maximum relative phase error in 2D. A Petrov-Galerkin
ormulation that yields the aforesaid scheme on structured meshes is also presented. Convergence studies of the
error in the L2 norm, the H1 semi-norm and the I ~ Euclidean norm is done and the pollution effect is found to be small.Presentamos tres nuevos metodos estabilizados de tipo Petrov- Galerkin basado en elementos finitos (FE) para los problemas de convecci6n-difusi6n- reacci6n (CDR), de Helmholtz y de Stokes, respectivamente. El trabajo comienza con un analisis a priori de un metodo de recuperaci6n de la consistencia de algunos metodos de estabilizaci6n que pertenecen al marco de Petrov-Galerkin. Hallamos que el uso de algunas de las practicas estandar (por ejemplo, la eoria de Matriz-M) para el diserio de metodos numericos esencialmente no oscilatorios no es apropiado cuando utilizamos los metodos de recu eraci6n de la consistencia. Por 10 tanto, con res ecto a la estabilizaci6n de conveccion, no preferimos tales metodos de recuperacion . A continuacion, presentamos el diser'io de un metodo de Petrov-Galerkin de alta-resolucion (HRPG) para el problema CDR. La estructura del metodo en 10 es identico al metodo CAU [doi: 10.1016/0045-7825(88)90108-9] excepto en la definicion de los parametros de estabilizacion. Esta estructura tambien se puede obtener a traves de la formulacion del calculo finito (FIC) [doi: 10.1 016/S0045- 7825(97)00119-9] usando una definicion adecuada de la longitud caracteristica. El prefijo de "alta-resolucion" se utiliza aqui en el sentido popularizado por Harten, es decir, tener una solucion con una precision de segundo orden en los regimenes suaves y ser esencialmente no oscilatoria en los regimenes no regulares. El diser'io en 10 se embarca en el problema de eludir el fenomeno de Gibbs observado en las proyecciones de tipo L2. A continuacion, estudiamos las condiciones de los parametros de estabilizacion para evitar las oscilaciones globales debido al ermino convectivo. Combinamos los dos resultados (una conjetura) para tratar el problema COR, cuya solucion numerica sufre de oscilaciones numericas del tipo global, Gibbs y dispersiva. Tambien presentamos una extension multidimensional del metodo HRPG utilizando los elementos finitos multi-lineales. fa. continuacion, proponemos un esquema compacto de orden superior (que incluye dos parametros) en mallas estructuradas para la ecuacion de Helmholtz. Haciendo igual ambos parametros, se recupera la interpolacion lineal del metodo de elementos finitos (FEM) de tipo Galerkin y el clasico metodo de diferencias finitas centradas. En 10 este esquema es identico al metodo AIM [doi: 10.1 016/0771 -050X(82)90002-X] y en 20 eligiendo el valor de 0,5 para ambos parametros, se recupera el esquema compacto de cuarto orden de Pade generalizada en [doi: 10.1 006/jcph.1 995.1134, doi: 10.1 016/S0045-7825(98)00023-1] (con el parametro V = 2). Seguimos [doi: 10.1 016/0045-7825(95)00890-X] para el analisis de este esquema y comparamos su rendimiento en las mallas uniformes con el de "FEM cuasi-estabilizado" (QSFEM) [doi: 10.1016/0045-7825 (95) 00890-X]. Presentamos expresiones genericas de los para metros que garantiza una precision dispersiva de sexto orden si ambos parametros son distintos y de cuarto orden en caso de ser iguales. En este ultimo caso, presentamos la expresion del parametro que minimiza el error maxima de fase relativa en 20. Tambien proponemos una formulacion de tipo Petrov-Galerkin ~ue recupera los esquemas antes mencionados en mallas estructuradas. Presentamos estudios de convergencia del error en la norma de tipo L2, la semi-norma de tipo H1 y la norma Euclidiana tipo I~ y mostramos que la perdida de estabilidad del operador de Helmholtz ("pollution effect") es incluso pequer'ia para grandes numeros de onda. Por ultimo, presentamos una coleccion de metodos FE estabilizado para el problema de Stokes desarrollados a raves del metodo FIC de primer orden y de segundo orden. Mostramos que varios metodos FE de estabilizacion existentes y conocidos como el metodo de penalizacion, el metodo de Galerkin de minimos cuadrados (GLS) [doi: 10.1016/0045-7825(86)90025-3], el metodo PGP (estabilizado a traves de la proyeccion del gradiente de presion) [doi: 10.1 016/S0045-7825(96)01154-1] Y el metodo OSS (estabilizado a traves de las sub-escalas ortogonales) [doi: 10.1016/S0045-7825(00)00254-1] se recuperan del marco general de FIC. Oesarrollamos una nueva familia de metodos FE, en adelante denominado como PLS (estabilizado a traves del Laplaciano de presion) con las formas no lineales y consistentes de los parametros de estabilizacion. Una caracteristica distintiva de la familia de los metodos PLS es que son no lineales y basados en el residuo, es decir, los terminos de estabilizacion dependera de los residuos discretos del momento y/o las ecuaciones de incompresibilidad. Oiscutimos las ventajas y desventajas de estas tecnicas de estabilizaci6n y presentamos varios ejemplos de aplicacion
24
Auld, Kathleen. "Can port state measures taken against RMFO partners be reconciled with international trade law? a critical analysis of the EU shared stocks regulation in light of the herring dispute." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20791.
Full textAbstract:
The European Union (EU) and Faroe Islands, a small self-governing archipelago under the sovereignty of Denmark, both belong to the North-East Atlantic Fisheries Commission (NEAFC). NEAFC is a regional fisheries management organisation (RFMO) which is responsible for the management of, inter alia, Atlanto-Scandian herring. NEAFC parties have a long-term management plan in place for Atlanto-Scandian herring. Based on recommendations from the International Council for the Exploration of Seas (ICES) the parties set a total allowable catch (TAC) for the herring and divide this among the contracting parties each year. At the 2012 consultations between the NEAFC parties the Faroe Islands requested a larger share of the TAC. The Faroe Islands left the consultations after the other parties repeatedly refused this request. It was granted a share of the TAC by the other four states in its absence. It then set its own catch quota far above this allocated share. In response the EU put in place port state measures to prevent Atlanto-Scandian herring from entering the EU. This included an import ban and a ban on the use of EU ports by Faroese vessels. The EU took this action under Council Regulation (EC) No. 1026/2012 (Shared Stocks Regulation) which allows measures to be imposed against third countries that allow non-sustainable fishing of common or straddling stocks. This includes measures taken against RFMO partners for non-compliance with RMFO laws, as RFMOs are generally set up to conserve straddling fish stocks. This Regulation was promulgated in line with a number of multilateral environmental agreements (MEAs) such as UNCLOS and the United Nations Fish Stocks Agreement (UNFSA). The Faroe Islands challenged the Shared Stocks Regulation and the specific Implementing Regulation imposing the port state measures in both the World Trade Organisation (WTO) and a Tribunal constituted under the United Nations Convention on the Law of the Sea (UNCLOS). However the matter was settled before either of these tribunals could hear the case. The dissertation interrogates whether the EU Regulations are consistent with WTO law, specifically the General Agreement on Tariffs and Trade (GATT), using the facts of the Atlanto-Scandian herring dispute. Chapter I sets out the background to the dispute, and explains the concepts of illegal, unreported and unregulated (IUU) fishing, and port state measures. Chapters II and III of the dissertation consider the consistency of the EU Regulations with the GATT. Chapter II finds that the EU Regulations contravene one or more of Articles I, V and XI of the GATT (the substantive provisions). Chapter III considers whether these measures, having contravened one of the GATT substantive provisions, may be justified under Article XX of the GATT (the exceptions provision). Chapter III concludes that, although well-crafted, the EU Regulations may still not be justifiable under the Article XX Chapeau in the particular circumstances of the herring dispute, based on principles in previous WTO cases. Chapter IV considers the relationship between multilateral environmental agreements (MEAs) relevant to IUU fishing and WTO agreements, to determine whether the EU Regulations could be considered GATT-consistent by reference to these MEAs or whether the MEAs could override WTO law. Chapter V concludes.
25
Ntovas, Alexandros. "Compulsory settlement of compatibility fishery disputes : the theory of embedded clauses in article 7 of the agreement for the implementation of the provisions of the United Nations Convention on the Law of the Sea of 10 December 1982 relating to the conservation and management of straddling fish stocks and highly migratory fish stocks." Thesis, University of Southampton, 2011. https://eprints.soton.ac.uk/345561/.
Full textAbstract:
The 1995 UN Fish Stocks Agreement established the principle of compatibility envisaging that conservation and management measures adopted within national Exclusive Economic Zones and those adopted on the adjacent high seas should be compatible. However, the aforementioned principle has been regarded as representing one of the most contentious elements in the new law of the sea régime. The ambiguity lies in the existent legal uncertainty about the measures which shall be regarded as the referential basis for international regulatory schemes. The above controversy becomes more acute in the shade of the doubtful application that the available disputes settlement provisions under the 1982 UN Convention on the Law of the Sea might have on this kind of disputes. The present disquisition studies the rationale behind an obscure system of clausal construction which was conceived by, and for first time emerged from the drafts of, the UN International Law Commission in early 1950s. This clausal construction refers to the peculiar pattern of legal drafting wherein procedural clauses are amalgamated into articles of substantive law. It is argued that treaty articles containing such clauses are predisposed to establish an inextricable connection between the substantive provisions and the provisions of procedure for the settlement of disputes. This kind of blended provisions represents a sui generis law, the peculiarity of which derives from its own insusceptibility to State auto-interpretation. The purpose of this analysis is to argue in favour of the compulsory application of the 1995 UN Fish Stocks Agreement's settlement procedures on compatibility disputes in remaining unaffected by the operation of the procedural limitation. In advancing this argument the present thesis aims at developing a theory over the functional role of the procedural clauses which initially seem that for no obvious reason have been extracted from Part VIII of the Agreement and been embedded into the substantive article of compatibility. By analysing thus the textual formation of embedded clauses the present thesis constructs its argument upon – and further advances – an existing proposition in the literature that views compulsory dispute settlement procedures as indispensable element of the substantive principle insofar as compatibility is vaguely construed in neutral terms; i.e., without a predetermined orientation in its geographical scope.
26
Guillard, Jean. "Etude des stocks pisciaires lacustres par échointégration : problèmes méthodologiques." Lyon 1, 1991. http://www.theses.fr/1991LYO10092.
Full textAbstract:
L'echosondage et l'echointegration sont de plus en plus utilises pour reperer, decrire et estimer les stocks pisciaires. Trois disciplines a priori tres distantes, l'acoustique, la statistique et la biologie, convergent ainsi en un ensemble interdependant dans la mise en uvre et pour la reussite des operations. Par suite de la complexite des techniques utilisees dans le recueil et dans l'exploitation des resultats, la methode est d'emploi delicat et susceptible d'engendrer de nombreuses erreurs. L'objet de cette these est de presenter les problemes techniques et methodologiques rencontres lors de l'echosondage en lac, de proposer des solutions et d'en demontrer le resultat dans le cas concret d'un suivi sur quatre annees du stock pisciaire d'un lac alpin. Dans une premiere partie sont rappeles les grands principes des methodes utilisees. Dans la deuxieme partie les differents problemes rencontres lors de l'etablissement des plans d'echantillonnage d'une campagne d'echointegration en lac, en fonction des repartitions spatio-temporelles des peuplements piscicoles, des differences jour-nuit, sont developpes ainsi que la maniere dont nous les avons resolus. La modelisation des structures des peuplements de poisson par l'intermediaire des variogrammes est analysee en fonction des contraintes dues a la particularite des peuplements lacustres. En troisieme partie, le bilan de quatre annees consecutives de campagnes sur le lac d'annecy est presente; il permet d'etudier un cas concret et de comparer les methodes geostatistiques avec une approche statistique parametrique. Les conclusions portent sur l'interet de cette convergence de disciplines dans la methode etudiee pour la gestion piscicole des lacs et pour des etudes plus ponctuelles sur les ecosystemes lacustres
27
Frankiewicz, Christophe. "Etude analytique, numérique et expérimentale d’écoulements générés par parois mobiles en microfluidique - Application aux micropompes." Thesis, Ecole centrale de Lille, 2012. http://www.theses.fr/2012ECLI0018/document.
Full textAbstract:
A l’heure actuelle, la microfluidique est une science en plein développement ayant un besoin croissant de dispositifs permettant de générer des écoulements aux échelles micrométriques. Les phénomènes physiques mis en jeu lors du mouvement d’un fluide sont en effet majoritairement gouvernés par la viscosité (bas nombre de Reynolds) contrairement aux écoulements macroscopiques dominés par les effets inertiels.Dans cette thèse, les écoulements engendrés par le mouvement de parois mobiles ont été étudiés en vue d’une application aux micropompes, dispositifs essentiels en microfluidique.Dans une première partie, une étude analytique et numérique évalue la possibilité de générer un écoulement par un cylindre en rotation à proximité de parois mobiles.Les résultats obtenus du régime de Stokes (Re=0) jusqu’à un nombre de Reynolds Re=60 en régime stationnaire témoignent du potentiel notable d’intégration de cette géométrie dans les microsystèmes en tant que micropompes.Dans une seconde partie, une micropompe, basée sur un principe de fonctionnement novateur, est conçue par l’intermédiaire des techniques de microfabrication. Dans cette optique, le procédé de gravure RIE d’un élastomère est entièrement développé. Les performances de la micropompe en terme de pression et débit générés dépassent l’état de l’art des microsystèmes similaires et ceci en utilisant une technologie simple et bas-coûtCurrently, microfluidic is a science field in constant development with an increasing need of devices able to generate flows at the micrometer order. At these length scales, physical phenomenons occurring in a moving fluid are mainly governed by its viscosity (low Reynolds number) contrary to macroscale flows dominated by inertial effects.In this thesis, a study on flows engendered by moving walls has been carried to fulfill to micropumps devices.In a first part, an analytical and a numerical study evaluates the possibility to generate a flow for a rotating cylinder close to moving boundaries.The results ranging from Stokes flows (Re=0) up to the low Reynolds number Re=60 in the stationary regime reveals the noticeable potential of integrating this device in microsystems as a micropump. In a second part, a new micropump, based on an innovative principle, is designed thanks to microfabrication technologies. In this perspective, the etching process of an elastomer called Silastic S is developed. Micropump performances in terms of pressure and flow rate are beyond the state of the art for similar microsystems and are achieved by using a simple and low-cost technology
28
Jonas, Ejner. "Livsmedelsbutikers avfallshantering : Avfallshantering och bortforsling av avfall hos livsmedelsbutiker i Örnsköldsvik och Kramfors kommun." Thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-123130.
Full textAbstract:
The purpose of this report was to find out if grocery stores in Örnsköldsvik and Kramfors municipality recycle their producer responsibility package waste, hazardous waste and their food waste and in what way they get rid of their waste. Are there any differences in how these two municipalities does it? Are there any variance between different stores depending on size, location and finally come up with suggestions for improvements. To find out the answer to this questions phone interviews with 25 grocery stores in these two municipalities were conducted. The results from the survey shows that grocery stores in both municipalities sort out their producer responsibility package waste and hazardous waste to a great extent. Only four stores indicated that they sorted out food waste. Responses were varied regarding in what way the grocery stores get rid of their waste. Some stores get their waste picked-up by the municipality and others by different entrepreneurs. One of the big food chains have a contract with an entrepreneur to pick up their waste at all the stores in this part of the country. Some of the suggested improvements are to minimize the amount of food waste that gets thrown away and clarify the laws on what waste that the municipality have monopoly on. The conclusion of this report is that grocery stores in these two municipalities are good at sorting out their waste except food waste.
29
Genc, Balkan Ziya. "Implementation And Comparison Of Turbulence Models On A Flat Plate Problem Using A Navier-stokes Solver." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1096668/index.pdf.
Full textAbstract:
For turbulent flow calculations, some of the well-known turbulence models in the literature are applied on a previously developed Navier-Stokes solver designed to handle laminar flows. A finite volume formulation, which is cell-based for inviscid terms and cell-vertex for viscous terms, is used for numerical discretization of the Navier-Stokes equations in conservative form. This formulation is combined with one-step, explicit time marching Lax-Wendroff numerical scheme that is second order accurate in space. To minimize non-physical oscillations resulting from the numerical scheme, second and fourth order artificial smoothing terms are added. To increase the convergence rate of the solver, local time stepping technique is applied.
Before applying turbulence models, Navier-Stokes solver is tested for a case of subsonic, laminar flow over a flat plate. The results are in close agreement with Blasius similarity solutions.
To calculate turbulent flows, Boussinesq eddy-viscosity approach is utilized. The eddy viscosity (also called turbulent viscosity), which arises as a consequence of this approach, is calculated using Cebeci-Smith, Michel et. al., Baldwin-Lomax, Chien&rsquos k-epsilon and Wilcox&rsquo
s k-omega turbulence models. To evaluate the performances of these turbulence models and to compare them with each other, the solver has been tested for a case of subsonic, laminar - transition fixed - turbulent flow over a flat plate. The results are verified by analytical solutions and empirical correlations.
30
Munuo, Ngaya Anael. "Towards the design of a reflexive regulatory framework to "Reduce and control emissions from land deforestation and degradation and enhancing carbon stocks" (REDD+): a perspective from select developing countries." Doctoral thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/23656.
Full textAbstract:
REDD+ has emerged as one of the governance approaches to address climate change. It calls for developing countries to take part in a second commitment period for a post-2020 climate change regime under the auspices of the United Nations Framework Convention on Climate Change (UNFCCC) and outside the UNFCCC. The goal of REDD+ is that host countries will receive, inter alia, financial compensation if they choose to conserve their forests rather than convert them to non-forest land use. Such compensation is for significant emission reductions which are reasonably attributable to human activities. This implies that REDD+ implementation at a domestic level will require allocation of burdens and benefits. In light of this implication, many scholars suggest that the design of the policy and legal framework to this effect must strike a balance between equity, environmental effectiveness and costeffectiveness (commonly referred to as the 3Es) to be deemed successful. Against this background, this thesis questions: what is the optimal (and feasible) model legislative framework sufficient to implement REDD+? It argues that REDD+ should be defined as a self-regulatory system. This view directs attention toward a distinctive regulatory framework. Thus the thesis suggests that one possible legal framework that holds that potential in Tanzania and Indonesia is reflexive law. The research draws on international best practice and numerous innovative governance models from different fields and proposes essential elements to substantiate its position.
This study reflects REDD+ developments up to 31 December 2015.
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Mercier, Fabienne. "Modélisation numérique de l'érosion d'un sol cohésif par un écoulement turbulent." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4718/document.
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Les mécanismes d'érosion sont la principale cause de rupture des ouvrages hydrauliques en remblai, c'est pourquoi il est capital de pouvoir quantifier la résistance des sols à l'érosion. Divers appareillages permettent d'en obtenir une estimation, notamment le Jet Erosion Test (JET) dont le modèle d'interprétation est empirique. L'objectif de ce travail est de statuer sur la pertinence ce modèle d'interprétation. Pour cela, nous avons développé un modèle numérique 2D de type Navier-Stokes turbulent avec déplacement d'interface et remaillage, permettant de modéliser l'érosion d'un sol cohésif par un écoulement turbulent. En injectant dans notre modèle les paramètres d'érosion trouvés à la suite d'essais de JET, on retrouve numériquement l'évolution de la profondeur d'affouillement obtenue expérimentalement. Nous avons appliqué cette méthode à trois différents essais de JET, les résultats obtenus sont en bon accord avec les résultats expérimentaux. En plus d'une importante étude paramétrique, ces résultats ont permis d'apporter d'importants éléments de validation au modèle d'interprétation du JET. Pour étendre le champ d'applicabilité du modèle, nous avons également appliqué cette méthode de modélisation à la configuration de l'érosion de conduit. Trois essais de Hole Erosion Test (HET) ont été modélisés et nous avons également obtenus des résultats en bon accord avec les résultats expérimentaux. Une analyse de la loi d'érosion et des paramètres d'érosion obtenus à la suite d'essais de JET et de HET a ensuite été initiée. Les bases d'une étude portant sur l'influence de l'angle d'incidence de l'écoulement, sur l'efficacité de l'érosion, ont été poséesErosion mechanisms are the main cause of hydraulic failure in embankments. Therefore, the resistance of soils to erosion must be quantified. To this hand, several devices are used such as the Jet Erosion Test (JET), whose model of interpretation is strongly empirical. The aim of this study is to determine the relevance of the interpretation model of the JET. For this purpose, a 2D Navier-Stokes numerical model of erosion of cohesive soils by a turbulent flow has been proposed. We first developed and implemented an interface movement model, whose input parameters are the erosion parameters found experimentally by JET test. Then, the scour depth evolutions obtained numerically for three JET test cases are compared to experimental data. Good agreement is obtained. A parametric study has also been conducted to validate the accuracy of the numerical results. These results contribute to the validation of the JET interpretation model. To extend its domain of application, we applied the numerical model to concentrated leak erosion during Hole Erosion Tests (HET). Three HET were modeled and, here again, our numerical results are in satisfactory agreement with the experimental results from the tests. An analysis of the erosion law and erosion parameters obtained with JET and HET was finally initiated. The potential influence of the flow incidence angle on the erosion efficiency was underlined
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Palmer, Darci Coleen. ""Food & Shelter": Low-Income Housing Tax Credit Developments in California and Access to Grocery Stores." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/561.
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Since the mid-century proliferation of public housing, policy makers and environmental justice advocates have exposed the fact that geographically and economically isolated public housing sites are ultimately detrimental to residents and communities. In recent years, more progressive housing policies have emphasized the importance of site location in the success of housing programs. This study explores the intersection of affordable housing policy and “food desert” research, by assessing the Low-Income Housing Tax Credit (LIHTC) program in California, with specific attention to the grocery store category within the Site Amenities section. Since the inception of the LIHTC program in 1986, the California Tax Credit Allocation Committee (CTCAC) has made multiple revisions to its application process. The study evaluates the current accessibility of grocery stores from LIHTC sites in Alameda and Santa Clara Counties in Northern California. It also critiques the changes in application scoring, criteria, and the indicators of food facility proximity and quality, identifying weaknesses, recommendations, and areas for further research.
It finds that despite CTCAC’s efforts to improve the effectiveness of the application, there does not seem to improvement in grocery store access over time. Further research is needed to determine whether this condition is a result of a failure on the part of the application process, or of high land costs and limited availability of developable land.
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Mezemate, Yacine. "Analyse et modélisation multifractales des interactions ondes-turbulence-biologie dans un lac urbain." Thesis, Paris Est, 2014. http://www.theses.fr/2014PEST1166/document.
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Les recherches en milieu lacustre ont généralement porté sur les grands lacs naturels et les barrages. Or les défis scientifiques que présentent les lacs urbains sont nombreux du fait de leur faible profondeur et de leur extension .Le travail que nous présentons ici s'inscrit dans le cadre du projet Petits Lacs Urbains Mesures Modèles Multi-Echelles (PLUMMME), projet financé par la région Île-de-France (programme DIM R2DS).Ce projet a permis l'équipement du lac de Créteil en mesures à haute résolution. Ce sont ces mesures physiques et biologiques qui sont essentiellement exploitées dans cette thèse, parfois en comparaison avec celles du lac du Bourget. La première étape de cette thèse a été ainsi d'enrichir la base de données déjà disponible. Pour cela, nous avons mis en place une station de mesure en continu (capteurs de température, chlorophylle et luminosité, données météorologique telles que vitesse du vent et température atmosphérique), ainsi que deux chaînes de mesures comportant différents capteurs. Des campagnes de mesures spécifiques ont également été réalisées pour l'étude de hydrodynamique à l'aide d'un courantomètre de type Acoustic Doppler Velocimeter (ADV), ainsi qu'un profileur de type Acoustic Doppler Current Profilers (ADCP) à deux points différents du lac (point central et point du rejet d'eaux pluviales). L'analyse des différents champs montre que le lac présente des stratifications avec une période d'une semaine. Nous avons également identifié les modes d'oscillations des ondes internes lorsque ces dernières se produisent sous l'effet du vent. L'analyse spectrale a permis de mettre en évidence une première propriété d'invariance d'échelle des différents champs mesurés. Les différents processus physique (turbulence, stratification, écoulement proche de la paroi) opérant le long de la colonne d'eau ont également été caractérisés. L'analyse spectrale ne permet pas de mettre en évidence le caractère intermittent des fluctuations des champs mesurés, ces dernières peuvent par contre être analysées à l'aide des techniques multifractales. Dans cette thèse nous avons montré que lorsqu'il existe une dépendance entre deux champs, celle ci est multi-échelle. L'utilisation du modèle multifractal universel (UM) a permis de quantifier le degré de cette dépendance. La qualité de l'estimation des paramètres UM dépend fortement de celle de l'invariance d'échelle observée: des séries temporelles présentant des tendances ne respectent pas cette invariance. Les effets de ces dernières sur l'estimation des paramètres UM peuvent être éliminés en utilisant la méthode de décomposition empirique modale dans l'espace physique. L'utilisation des données du champ de vitesse mesuré à l'aide de l'ADCP montre que, les pentes des spectres suivent un profil logarithmique selon la verticale, cela met en évidence que différents processus physiques opèrent le long de la colonne d'eau. Nous montrons également que l'hydrodynamique du lac est fortement perturbée à petite échelle au point du rejet d'eau pluviale. La dernière partie de la thèse examine ce que notre analyse à petites échelles apporte aux modèles numériques. Nous montrons que si les modèles déterministes arrivent à reproduire certains phénomènes à grande échelle, ils sont dans l'incapacité de représenter correctement les fluctuations à petites échelles, donc les processus physiques correspondants. L'analyse multifractale montre que la variabilité des champs physiques présente une forte intermittence. Le fait que la majorité des interactions biologiques/chimiques se produisent à petites échelles souligne la nécessité d'améliorer qualitativement les modèles de fermeture des équations de Navier-Stokes. Enfin, nous montrons que les fonctions de structures, observables statistiques de base en turbulence, ne permettent pas de caractériser de façon unique les champs non conservatifs et donc correspondent à des simulations multifractales non identiquesResearch in limnology has generally focused on natural lakes and dams. Moreover, the scientific challenges posed by urban lakes are numerous because of their large width and shallow depth resulting in complex problems that involve. This work is part of the project Petits Lacs Urbains Mesures Modèles Multi-Echelles (PLUMMME), founded by Région Île-de-France (DIM R2DS program). The project provides the high-resolution equipment measuring equipment used at Lake Créteil. Physical and biological measurements are the primary scope of this thesis, with some comparisons of measurements done between Lake Creteil and Lake Bourget. With this in mind, the first step of the thesis was to enhance currently available data. In order to do this we installed a station for the continuous measurement of: temperature, chlorophyll and light, also meteorological quantities such as wind speed, and air temperature were measured. The quantities were measured using two measuring chains comprising different sensors. Measurements were conducted in order to characterise hydrodynamics, using a current meter of type Acoustic Doppler Velocimeter (ADV) and a profiler of type Acoustic Doppler Current Profilers (ADCP) positioned at different points in the lake (centrally, and at the point of stormwater discharge). The analysis of the various measured fields shows that the lake is periodically stratified with a period of one week. We also identify the different modes of the internal waves that occur due to the effects of the wind. Spectral analysis was used to highlight the first scale invariant propriety of the different measured fields. Various physical processes (turbulence, stratification, near-wall flow) operating along the water column were also characterised using this method. The spectral analysis, however, does not provide information about the intermittency of the fluctuations of the measured fields, this can only be done using multifractal techniques. In this thesis, we have shown that when there is a dependence between two fields, the dependence is multiscale. The use of the Universal Multifractal (UM) model, allows one to quantify the degree of this dependence. The quality of the estimation of the UM parameters depends strongly on that of the observed scale: time-series with trends are not scaling. The effects of the latter on the estimation of UM parameters can be improved by the application of the Empirical Modal Decomposition method. The measured velocity data from the ADCP shows that the slope of the power spectra density follow a logarithmic profile along the depth of the lake, it shows that different physical processes operate along the water column. We also show that the hydrodynamics of the lake at small scale are strongly perturbed at the point of waterstorm discharge. The last part of the thesis is focused on what our analysis at small-scales brings to numerical models. We show that, if the deterministic models are able to reproduce some phenomena at large scale, they fail to describe the small-scale variability. the small scale variability and the physical processes involved. A multifractal analysis showed that the small-scale variability of the physical fields displays a strong intermittency, an extremely important feature for biological or chemical reactions and therefore for biological scenarios. Knowing that the majority of biological/chemical interactions occur at smaller scales, this result underlines the necessity to greatly improve the closure of the Navier-Stokes equations. Finally, we show that the structure function, a frequently used statistical tool in turbulence, do not uniquely characterize non-conservative fields, i.e., they do not correspond to identical simulations
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Brusewitz, Collin Emanuel, and Andreas Svensson. "The principal agent." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-12765.
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Problem: How can segments on Aktietorget explain how a lemon market can not only survive but grow? Purpose: The purpose is to try to explain how Aktietorget can grow under lemon market conditions by gauging investor groupings investment tendencies. Method: Quantitative archival study regarding returns and price per share depending on investor identity. Conclusion: Finance industry investor yields higher returns, which implicates the possibility of rational investing. This is attributed to either identity inherited capabilities or them being agents in the place of the principal. The private investor on the other hand is full principals and has a tendency towards low price per share. All other capital on Aktietorget conforms to the lottery characteristics of Aktietorget.
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AYYALASOMAYAJULA, HARITHA. "HIGHER-ORDER ACCURATE SOLUTION FOR FLOW THROUGH A TURBINE LINEAR CASCADE." University of Cincinnati / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1054757181.
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Springstube, Woodard R. (Woodard Rex). "Studies in Bank Contagion: Three Regulatory Events." Thesis, University of North Texas, 1998. https://digital.library.unt.edu/ark:/67531/metadc279347/.
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This research describes an analysis, using event-study methodology, of the reaction of the stock returns of a sample, drawn from the one-hundred largest bank holding companies, to certain actions of regulatory agencies. The first part of the analysis examines the reaction of the bank stocks to the closure of the Bank of New England, using cross-sectional variables not previously examined by other investigators. The second event considers the invalidation of interest-rate swap contracts by the British Law Lords, the highest court in Britain. The third case is an examination of the effects of actions taken to enforce the Community Reinvestment Act. All three events have significant abnormal returns in at least one sub-sample and event window. The results of the cross-sectional analysis and the lack of response to later events are consistent with market efficiency in the semi-strong form. The results are also consistent with the hypothesis that regulatory policies that emphasize consistency and banking system safety are desirable.
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Zhang, Zhen. "Some issues about E-commerce in the WTO framework with implications for China's laws." Bern : World Trade Institute (WTI), 2004. http://www.wti.org/images/stories/MILE/MILE%20Theses/Some%20Issues%20about%20E-Commerce%20in%20the%20WTO%20framework.pdf.
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Rumble, Tony Law Faculty of Law UNSW. "Synthetic equity and franked debt: capital markets savings cures." Awarded by:University of New South Wales. School of Law, 1998. http://handle.unsw.edu.au/1959.4/17591.
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Micro-economic reform is a primary objective of modern Australian socio-economic policy. The key outcome targetted by this reform is increased efficiency, measured by a range of factors, including cost reduction, increased savings, and a more facilitative environment for business activity. These benefits are sought by the proponents of reform as part of a push to increase national prosperity, but concerns that social equity is undermined by it are expressed by opponents of that reform. The debate between efficiency and equity is raging in current Australian tax policy, a key site for micro-economic reform. As Government Budget restructuring occurs in Australia, demographic change (eg, the ageing population) undermines the ability of public funded welfare to provide retirement benefits. Responsibility for self-funded retirement is an important contributor to increasing private savings. Investment in growth assets such as corporate stock is increasing in Australia, however concerns about volatility of asset values and yield stimulate the importance of investment risk management techniques. Financial contract innovation utilising financial derivatives is a dominant mechanism for that risk management. Synthetic equity products which are characterised by capital protection and enhanced yield are popular and efficient equity risk management vehicles, and are observed globally, particularly in the North American market. Financial contract innovation, risk management using financial derivatives, and synthetic equity products suffer from an adverse tax regulatory response in Australia, which deprives Australian investors from access to important savings vehicles. The negative Australian tax response stems from anachronistic legislation and jurisprudence, which emphasises tax outcomes based on legal form. The pinnacle of this approach is the tax law insistence on characterisation of financial contracts as either debt or equity, despite some important financial similarities between these two asset types. Since derivatives produce transactions with novel legal forms this approach is unresponsive to innovation. The negative tax result also stems from a perception that the new products are tax arbitrage vehicles, offering tax benefits properly available to investment in stocks, which is thought to be inappropriate when the new products resemble debt positions (particularly when they are capital protected and yield enhanced). The negative tax response reflects administrative concerns about taxpayer equity and revenue leakage. This approach seeks to impose tax linearity by proxy: rather than utilising systemic reform to align the tax treatment of debt and equity, the current strategy simply denies the equity tax benefits to a variety of innovative financial contracts. It deprives Australians of efficiency enhancing savings products, which because of an adverse tax result are unattractive to investors. The weakness of the current approach is illustrated by critical analysis of three key current and proposed tax laws: the ???debt dividend??? rules in sec. 46D Income Tax Assessment Act 1936 (the ???Tax Act???); the 1997 Budget measures (which seek to integrate related stock and derivative positions); and the proposals in the Taxation of Financial Arrangements Issues Paper (which include a market value tax accounting treatment for ???traded equity,??? and propose a denial of the tax benefits for risk managed equity investments). The thesis develops a model for financial analysis of synthetic equity products to verify the efficiency claims made for them. The approach is described as the ???Tax ReValue??? model. The Tax ReValue approach isolates the enhanced investment returns possible for synthetic equity, and the model is tested by application to the leading Australian synthetic equity product, the converting preference share. The conclusions reached are that the converting preference share provides the key benefits of enhanced investment return and lower capital costs to its corporate issuer. This financial efficiency analysis is relied upon to support the assertion that a facilitative tax response to such products is appropriate. The facilitative response can be delivered by a reformulation of the existing tax rules, or by systemic reform. The reformulation of the existing tax rules is articulated by a Rule of Reason, which is proposed in the thesis as the basis for the allocation and retention of the equity tax benefits. To avoid concerns about taxpayer equity and revenue leakage the Rule of Reason proposes a Two Step approach to the allocation of the equity tax benefits to synthetics. The financial analysis is used to quantify non-tax benefits of synthetic equity products, and to predict whether and to what extent the security performs financially like debt or equity. This financial analysis is overlayed by a refined technical legal appraisal of whether the security contains the essential legal ???Badges of Equity.??? The resulting form and substance approach provides a fair and equitable control mechanism for perceived tax arbitrage, whilst facilitating efficient financial contract innovation. The ultimate source of non-linearity in the taxation of investment capital is the differential tax benefits provided to equity and debt. To promote tax linearity the differentiation needs to be removed, and the thesis makes recommendations for systemic reform, particularly concerning the introduction of a system of ???Franked Debt.??? The proposed system of ???Franked Debt??? would align the tax treatment of debt and equity by replacing the corporate interest deduction tax benefit with a lender credit in respect of corporate tax paid. This credit would operate mechanically like the existing shareholder imputation credit. The interface of this domestic tax credit scheme with the taxation of International investment capital, and the problems occasioned by constructive delivery of franking credits to Australian taxpayers via synthetics, are resolved by the design and costings of the new system, which has the potential to be revenue positive.
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Koehler, Tanja. "Der Gleichbehandlungsgrundsatz bei Aktienemissionen /." Berlin : Duncker und Humblot, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014689414&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Schneider, Thomas. "Möglichkeiten und Grenzen der Umsetzung der gesellschaftsrechtlichen und bankenaufsichtsrechtlichen Anforderungen an Risikomanagement auf Gruppenebene /." Berlin : Duncker & Humblot, 2009. http://d-nb.info/997399570/04.
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Díaz, Caruajulca Mariela Marizel. "Propuesta de un sistema logístico para las empresas fabricantes de King Kong en la ciudad de Lambayeque." Bachelor's thesis, Universidad Católica Santo Toribio de Mogrovejo, 2015. http://tesis.usat.edu.pe/handle/usat/705.
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El presente trabajo consistió en desarrollar una propuesta de mejora en el sistema logístico en las empresas fabricantes de King Kong, en base a un diagnóstico que estableció el proceso logístico de (06) empresas fabricantes de King Kong en la ciudad, que se escogieron como población objetivo, que permitió apreciar cómo es su desarrollo logístico, si es eficiente o no lo es; cómo manejan las diferentes tareas que la conforman. Dentro de la metodología de la investigación se realizó una encuesta de opinión, mediante la cual se tomó en cuenta el punto de vista de los distribuidores en base a la relación con el fabricante y cómo se realiza la logística desde lo que ven ellos, y una entrevista a los representantes de las seis empresas fabricantes escogidas para obtener su opinión con respecto a su sistema logístico utilizado: si consideran que generan competitividad y productividad en el mercado. Así se generaron propuestas a los diferentes niveles y procesos en la logística de las empresas como: aprovisionamiento, compras, almacén, inventario, distribución y ventas. La presente investigación concluyó con encontrar ciertas deficiencias, por no contar con un sistema integrado, en la que cada una hace su parte y no un trabajo en conjunto, lo cual dificulta la incursión en nuevos mercados potenciales, que los clientes suelen fijarse y están muy pendientes en aspectos como la calidad, el precio y el tamaño del producto, por ser este representativo de la región, además de tener una relación no muy cercana con los distribuidores la cual dificulta aún más las operaciones del fabricante.Tesis
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Buoncristiani, Jean-François. "Production sédimentaire détritique des systèmes glaciaires. Quantification des produits stockés dans un lac proglaciaire durant la dernière glaciation : exemple du lac de la Combe d’Ain (Jura, France)." Dijon, 1997. http://www.theses.fr/1997DIJOS062.
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Cette thèse représente la quantification de la production sédimentaire détritique des systèmes glaciaires. L'objectif a été réalisé par l'étude d'un géosystème lacustre proglaciaire : le lac de la Combe d’Ain Jura, France). Le premier chapitre est consacré à l'analyse des différents processus d'érosion glaciaire actuels de façon qualitative et quantitative. Le chapitre 2 consiste à déterminer la surface du sous-système émetteur. Dans une première phase, le bassin-producteur supra-glaciaire est déterminé en fonction de la topographie de la surface glaciaire et des lignes d'écoulement. Puis, une seconde phase consiste à limiter le bassin sous-glaciaire en fonction de la topographie du substrat et de ses vallées. Dans le chapitre 3, l'organisation sédimentaire du sous-système récepteur est réalisé, ce qui permet de déterminer sa durée de fonctionnement. Le chapitre 4 représente la reconstruction de la géométrie des surfaces supérieures et inférieures du remplissage lacustre. Deux méthodes sont utilisées : une méthode directe (cartographie des témoins dans le remplissage), et une méthode géophysique indirecte (sismique réflexion haute résolution). Le chapitre 5 définit le bilan sédimentaire du géosysteme et permet le calcul des taux de stockage, puis des taux de production sédimentaire spécifique et de dénudation du géosysteme. Une comparaison avec le géosysteme lacustre de Chaillexon situé dans le jura et fonctionnant depuis 12 000 ans permet de définir les variations de la production sédimentaire au cours du dernier cycle climatique glaciaire-interglaciaire. On constate ainsi que la production sédimentaire durant la phase glaciaire est 100 fois supérieure a celle durant la phase interglaciaire. Il ressort de cette thèse la notion de rushes détritiques d'origine glaciaire, dont l'importance sur les exportations de matière dans les couloirs alluviaux et au-delà, sur les dépôts en domaine marin est à prendre en compte dans les bilans.
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Peluchon, Simon. "Approximation numérique et modélisation de l'ablation liquide." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0739/document.
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Lors de sa rentrée dans l’atmosphère d’une planète, un engin spatial subit un échauffement important dû aux frottements des gaz atmosphériques sur la paroi. Cette élévation de température conduit à une dégradation physico-chimique du bouclier thermique de l’objet constitué de matériaux composites. Un composite est constitué de divers matériaux qui s’ablatent différemment. Dans cette thèse, nous nous intéressons essentiellement à la fusion d’un matériau durant sa phase de rentrée atmosphérique. Nous sommes donc en présence de trois phases : solide, liquide et gaz. Pour simuler ce phénomène, des méthodes numériques robustes ont été mises au point pour calculer l’écoulement diphasique compressible autour de l’objet. Le couplage entre le solide et l’écoulement fluide a aussi été étudié. Les méthodes numériques développées durant cette thèse sont basées sur une approche volumes finis. Une stratégie de décomposition d’opérateurs est utilisée pour résoudre le modèle diphasique à cinq équations avec les termes de dissipation modélisant l’écoulement fluide. L’idée principale de cette décomposition d’opérateurs est de séparer les phénomènes acoustiques et dissipatifs des phénomènes de transport. Un traitement implicite de l’étape acoustique est réalisé tandis que l’étape de transport est résolue explicitement. Le schéma semi-implicite global est alors très robuste, conservatif et préserve les discontinuités de contact. Les conditions d’interface entre les domaines fluide et solide sont déduites des bilans de masse et d’énergie à la paroi. Le front de fusion est suivi explicitement grâce à une formulation ALE des équations. La robustesse de l’approche et l’apport de la formulation semi-implicite sont finalement démontrés grâce à des expériences numériques mono et bidimensionnelles sur maillages curvilignes mobilesDuring atmospheric re-entry phase, a spacecraft undergoes a sudden increase of the temperature due to the friction of atmospheric gases. This rise drives to a physical-chemical degradation of the thermal protective system of the object made of composite material. A composite is made of several materials with ablates differently. In this thesis, we mainly focus on the melting of an object during its re-entry phase. Therefore there are three phases: solid, liquid and gas phases. In order to simulate this phenomenon, robust numerical methods have been developed to compute a compressible multiphase flow. The coupling strategy between the solid and the fluid have also been studied. Solvers developed in the present work are based on Finite Volume Method. A splitting strategy is used to compute compressible two-phase flows using the five-equation model with viscous and heat conduction effects. The main idea of the splitting is to separate the acoustic and dissipative phenomena from the transport one. An implicit treatment of the acoustic step is performed while the transport step is solved explicitly. The overall scheme resulting from this splitting operator strategy is very robust, conservative, and preserves contact discontinuities. The boundary interface condition between the solid and the multiphase flow is enforced by mass and energy balances at the wall. The melting front is tracked explicitly using an ALE formulation of the equations. The robustness of the approach and the interest of the semi-implicit formulation are demonstrated through numerical simulations in one and two dimensions on moving curvilinear grids
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López, Velásquez Stephanie Gabriella. "Estrategias del Post venta en el valor de marca en la categoría Deco hogar en las tiendas por departamento." Universidad Peruana de Ciencias Aplicadas (UPC), 2020. http://hdl.handle.net/10757/652696.
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En los últimos años, la categoría Deco Hogar en las tiendas por departamento han comenzado a tener una tendencia mayor de compra. Asimismo, el proceso de compra de estos productos es categorizado como una venta planificada, no por impulso. En la actualidad, los analistas del mercado se enfocan en crear estrategias para que el cliente final considere dentro de su planificación la compra de productos de decoración para el hogar. Sin embargo, existe una teoría, respaldada por especialistas que ejercer un plan de venta, no solo debe enfocarse en la meta final de la compra, sino en la última que sería la postventa. Esta te permite en lograr una diferencia en el mercado, crear fidelidad y preferencia por el consumidor, ya que crea una línea adicional de comunicación el cuál te permite escuchar la opinión del servicio presentado y lograr mejoras en el. En este sentido, en la presente investigación se enfocará en resolver la hipótesis de si las estrategias de post venta como; Satisfacción del cliente, facilidad de acceso y manejo de quejas y reclamos influirían en el valor de la marca. Esta investigación lo enfocaremos en los productos de la categoría Deco hogar. La metodología a utilizar será cuantitativa y cualitativa. En la cualitativa, se hará 3 entrevistas a especialistas y 2 Focus group con un total de 12 personas. Por otro lado, la cuantitativa será de 250 encuestas al público dirigido del servicio.
El resultado de esta investigación, gracias a un modelo de regresión lineal múltiple se pudo resolver el fenómeno de la influencia de las estrategias de la post venta en el valor de marca. Dando como resultado, ser de un carácter concluyente. De acuerdo antiguas investigaciones de las variables y de los resultados obtenidos en el análisis cuantitativo se pudo tener el mismo acuerdo, de que la variable dependiente Valor de marca influiría en las independientes que serían las estrategias de la post venta. Por último, los comentarios que se harían a la gerencia de cualquier tipo de comercio, es la recomendación de utilización de esta estrategia, ya que está comprobado que aplicaría un incremento en volúmenes de venta y fidelización del cliente en gran medida. Por último, para una mejor investigación de estrategias a utilizar en el post venta, se podría realizar una investigación más profunda, segmentando grupos y cambiando de variables como garantías, calidad de servicio, etc.In recent years, the Deco Home category in department stores has begun to have a higher buying trend. Also, the purchase process of these products is categorized as a planned sale, not by impulse. Currently, market analysts focus on creating strategies for the end customer to consider within their planning the purchase of home décor products. However, there is a theory, backed by specialists that exercise a sales plan, should focus not only on the final goal of the purchase, but on the last one that would be the after-sales. This allows you to make a difference in the market, create loyalty and preference for the consumer, since it creates an additional line of communication which allows you to listen to the opinion of the service presented and achieve improvements in it. In this sense, this research will focus on resolving the hypothesis of whether post-sales strategies as; Customer satisfaction, ease of access and handling of complaints and complaints would influence the value of the brand. This research will focus on products in the Deco home category. The methodology to be used will be quantitative and qualitative. In the qualitative, there will be 3 interviews with specialists and 2 Focus group with a total of 12 people. On the other hand, the quantitative will be 250 surveys to the targeted public of the service. The result of this research, thanks to a model of multiple linear regression, was able to solve the phenomenon of the influence of post-sales strategies on brand value. Resulting in being conclusive. According to previous investigations of the variables and the results obtained in the quantitative analysis, the same agreement could be had, that the dependent variable Brand value would influence the independent ones that would be the post-sales strategies. Finally, the comments that would be made to management of any type of trade, is the recommendation to use this strategy, since it is proven that it would apply an increase in sales volumes and customer loyalty to a large extent. Finally, for better research of strategies to be used in the post-sales, further research could be carried out, segmenting groups and changing variables such as guarantees, quality of service, etc.
Tesis
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Dehaoui, Amine. "Viscosité de l'eau surfondue." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10172/document.
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L'eau est un liquide omniprésent, son omniprésence n'a d'équivalence que la multitude de ses secrets. En effet, dans le cas de l'eau, le comportement de nombreuses grandeurs thermodynamiques et dynamiques se différencie de celui des liquides « standard ». Cette différence est d'autant plus importante dans l'état dit surfondue. Dans cette thèse, on s'intéresse à la viscosité de l'eau légère et lourde dans l'état surfondue à pression atmosphérique. Pour ce faire, nous avons utilisé la méthode de microscopie dynamique différentielle. Nous avons ainsi pu mesurer la viscosité jusqu'à -34°C pour l'eau légère et -25°C pour l'eau lourde. Ces mesures de viscosité corrélées à des mesures de coefficient d'auto-diffusion nous ont permis de confirmer l'existence d'une anomalie dite violation de Stokes-EinsteinWater is an omnipresent liquid, indeed secrets of water are uncountable. In the water case, the behaviour of many thermodynamical and dynamicalquantities is very different from other standard liquids. This difference is more important in the supercooled state. In this thesis we focus on the viscosity of the heavy and light water into the supercooled state at atmospheric pressure. To do this we use the differential dynamic microscopy method. We were able to measure the viscosity to -34 C for light water and -25°C for heavy water. These viscosity measurements correlated to measurements of self-diffusion coefficient allowed us to confirm the existence of a so-called anomaly violation Stokes-Einstein
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Corrêa, Laís. "Um novo esquema upwind de alta resolução para equações de conservação não estacionárias dominadas por convecção." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-12052011-084444/.
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Neste trabalho apresenta-se um novo esquema prático tipo upwind de alta resolução, denominado EPUS (Eight-degree Polynomial Upwind Scheme), para resolver numericamente equações de conservação TVD e é implementado no contexto do método das diferenças finitas. O desempenho do esquema é investigado na resolução de sistemas hiperbólicos de leis de conservação e escoamentos incompressíveis complexos com superfícies livres. Os resultados numéricos mostraram boa concordãncia com outros resultados numéricos e dados experimentais existentesIs this work a new practical high resolution upwinding scheme, called EPUS (Eight-degree Polynomial Upwind Scheme), for the numerical solution of transient convection-dominated conservation equations is present. The scheme is based on TVD stability criterion and is implemented in the context of the finite difference methodology. The performance of the scheme is investigated by solving hyperbolic systems of conservation laws and complex incompressible flows with free surfaces. The numerical results displayed good agreement with other existing numerical and experimental data
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Garcia, Gonzalez Jesus. "Numerical analysis of fluid motion at low Reynolds numbers." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/numerical-analysis-of-fluid-motion-at-low-reynolds-numbers(4cf30194-0155-439d-879a-c49787549e8c).html.
Full textAbstract:
At low Reynolds number flows, the effect of inertia becomes negligible and the fluid motion is dominated by the effect of viscous forces. Understanding of the behaviour of low Reynolds number flows underpins the prediction of the motion of microorganisms and particle sedimentation as well as the development of micro-robots that could potentially swim inside the human body to perform targeted drug/cell delivery and non-invasive microsurgery. The work in this thesis focuses on developing an understanding in the mathematical analysis of objects moving at low Reynolds numbers. A boundary element implementation of the Method of regularized Stokeslets (MRS) is applied to analyse the low Reynolds number flow field around an object of simple shape (sphere and cube). It also showed that the results obtained by a boundary element implementation for an unbounded cube, where singularities are presented in the corners of the cube, agrees with more complex solutions methods such as a GBEM and FEM.A methodology for analysing the effect of walls by locating collocation points on the surface of the walls and the object is presented. First at all, this methodology is validated with a boundary element implementation of the method of images for a sphere at different locations. Then, the method is extended when more than one wall is presented. This methodology is applied to predict the velocity filed of a cube moving in a tow tank at low Reynolds numbers for two different cases with a supporting rod similar to an experimental set-up, and without the supporting rod as in the CFD simulations based on the FVM. The results indicate a good match between CFD and the MRS, and an excellent approximation between the MRS and experimental data from PIV measurements. The drag, thrust and torque generated by helices moving at low Reynolds numbers in an unbounded medium is analysed by the resistive force theory, a slender body theory, and a boundary element method of the MRS. The results show that the resistive force theory predict accurately the drag, thrust and torque of moving helices when the resistive force coefficients are calculated from a slender body theory approximation by calculating independently the resistive force coefficients for translation and rotation, because it is observed that the resistive force coefficients depend also of the nature of motion. Moreover, the thrust generated by helices of different pitch angles is analysed calculated by a CFD numerical simulation based on the FVM and a boundary element implementation, an compared with experimental data. The results also show an excellent prediction between the boundary element implementation, the CFD results and the experimental data. Finally, a boundary element implementation of the MRS is applied to predict swimming of a biomimetic swimmer that mimics the motion of E.coli bacteria in an unbounded medium. The results are compared with the propulsive velocity and induced angular velocity measurement by recording the motion of the biomimetic swimmer in a square tank. It is observed that special care needs to be taken when the biomimetic swimmer is modelled inside the tank, as there is an apparent increment in the calculate thrust propulsion which does not represent a real situation of the biometic swimmer which propels by a power supply. However, this increment does not represent the condition of the biomimetic swimmer and a suggested methodology based on the solution from an unbounded case and when the swimmer is moving inside the tank is presented. In addition, the prediction of the free-swimming velocity for the biomimetic swimmer agrees with the results obtained by the MRS when the resistive force coefficients are calculated from a SBT implementation. The results obtained in this work have showed that a boundary element implementation of the MRS produces results comparable with more complex numerical implementations such as GBEM, FEM, FVM, and also an excellent agreement with results obtained from experimentation. Therefore, it is a suitable and easy to apply methodology to analyse the motion of swimmers at low Reynolds numbers, such as the biomimetic swimmer modelled in this work.
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Osorio, Bravo Milena Xiomara. "Los elementos de promoción en relación a la recompra en los sitios web de las tiendas por departamento en la categoría moda en e-commerce por parte de mujeres de 25 a 35 años de edad de NSE B en la zona 7 de Lima Metropolitana." Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2019. http://hdl.handle.net/10757/627761.
Full textAbstract:
El presente informe describe como los elementos de promoción influyen en la recompra en los sitios web de las tiendas por departamento en la categoría moda en mujeres de 25 a 35 años de edad en Lima Metropolitana.
Esta investigación se desarrolló entorno al análisis que se hizo del tema previamente y a la información encontrada, donde se pudo detectar factores relevantes en la plataforma digital, que incentivan a la recompra en el comercio electrónico.
Por ello, se hizo un análisis para identificar entre los factores más relevante para los consumidores cuando compraban en un sitio web, y porque esto generaba recompra en la plataforma digital. Además, de crear cercanía con el cliente, ya que no hay un contacto físico, por tanto, es necesario generar confianza en el usuario para que compre en el sitio web.
Durante la investigación se analizaron dos factores importantes para el consumidor y para las tiendas por departamento como estrategia para que el cliente regrese a la plataforma a comprar. Hablamos de los elementos de promoción y la información brindada por mailing a los usuarios. Asimismo, se detectaron factores que no se habían considerado inicialmente en el estudio, pero que formaban parte importante en la recompra por internet; como el caso del servicio post venta.
Para finalizar, se contrastan hallazgos encontrados en el campo cualitativo y cuantitativo de la investigación, más la información recopilada. Con esto se pudo profundizar y proponer estrategias para mejorar la compra en el canal virtual de las tiendas por departamento.This report describes how the promotional elements influence the repurchase on the websites of the department stores in the fashion category for women between 25 and 35 years of age in Metropolitan Lima. This research was developed around the analysis that was made of the subject previously and the information found, where it was possible to detect relevant factors in the digital platform, which encourage re-purchase in electronic commerce. Therefore, an analysis was made to identify among the most relevant factors for consumers when they were shopping on a website, and because this generated a repurchase on the digital platform. In addition, to create closeness with the client, since there is no physical contact, therefore, it is necessary to generate trust in the user to buy on the website. During the investigation, two important factors were analyzed for the consumer and department stores as a strategy for the client to return to the platform to buy. We talk about the promotion elements and the information provided by mailing to the users. Also, factors that had not been considered initially in the study, but that were an important part of the online buyback, were detected; as the case of after sales service. Finally, we compare findings found in the qualitative and quantitative field of the research, plus the information collected. With this it was possible to deepen and propose strategies to improve the purchase in the virtual channel of department stores.
Trabajo de investigación
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Smit, Jacobus Gideon. "Analysis of the interaction between the income tax and capital gains tax provisions applicable to share dealers." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85830.
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Thesis (MAccounting)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The interaction between the income tax provisions contained in sections 9B, 9C, 11(a) and 22 of the Income Tax Act No. 58 of 1962 (the Act), and the capital gains tax (CGT) provisions of the Eighth Schedule of the Act, are complex and share dealers should approach the tax consequences of share dealing profits with caution. The objective of the assignment was to ensure that the share dealing profits of share dealers (who transact on revenue account) are taxed correctly, with specific reference to the interaction between the aforementioned provisions. This was achieved by considering tax cases, the interpretation notes of the South African Revenue Services (SARS) and commentary of tax writers. Examples of share disposals were incorporated to illustrate that consistency is required between the calculation of profits for income tax and CGT purposes. The guidelines laid down by case law to determine the revenue nature of share disposals were investigated. It was concluded that share dealing profits which are designedly sought for and worked for, either as part of a business operation or not, are of a revenue nature and taxable as such. The method of identification of shares sold as trading stock is important when calculating the income tax profit, since it is used in order to determine both which shares are sold as well as the cost of the shares sold. It was concluded that the method of identification applied in terms of generally accepted accounting practice (GAAP) is generally also acceptable from an income tax perspective. Section 9C of the Act provides a share dealer income tax relief when a ‘qualifying share’ is disposed of. Any amount received or accrued as a result of the disposal of a qualifying share is deemed to be of a capital nature, regardless of the revenue intention of the share dealer. Prior to 1 October 2007, section 9B of the Act provided similar relief to the disposal of an ‘affected share’. It was concluded that section 9C of the Act has a wider scope of application compared to section 9B of the Act. Because the proceeds received on the disposal of affected or qualifying shares are excluded from gross income, the acquisition costs previously incurred and deducted in respect of such shares must be included in taxable income. It was determined that the amount to be included in income is the actual cost of such shares and not the opening trading stock value determined in terms of GAAP and claimed in terms of section 22(2) of the Act. It was concluded that the first-in-first-out (FIFO) method of identification should be applied to determine which affected or qualifying shares have been disposed of. From a CGT perspective, it was illustrated that a share dealer loses the opportunity to choose which identification method to apply and is obliged to also apply the FIFO method in calculating the CGT base cost of the shares. It is concluded that the Eighth Schedule of the Act should be amended to clarify that the FIFO method should be applied for CGT purposes where sections 9B or 9C of the Act find application. Only then will the tax profits of a share dealer be in sync with his or her cash benefit.
AFRIKAANSE OPSOMMING: Die interaksie tussen die inkomstebelastingbepalings vervat in artikels 9B, 9C, 11(a) en 22 van die Inkomstebelastingwet No. 58 van 1962 (die Wet), en die kapitaalwinsbelastingbepalings (KWB bepalings) van die Agtste Bylae tot die Wet is kompleks en aandelehandelaars moet die belastinggevolge van aandelewinste met omsigtigheid benader. Die doelwit van die werkstuk was om te verseker dat die winste van aandelehandelaars (wat aandele verkoop op inkomsterekening) korrek belas word, met spesifieke verwysing na die interaksie tussen die voorgenoemde bepalings. Dit is bereik deur die oorweging van hofsake, uitlegnotas van die Suid-Afrikaanse Inkomstediens en kommentaar deur belastingskrywers. Voorbeelde van aandeleverkope is gebruik om te illustreer dat konsekwentheid tussen die berekening van winste vir inkomstebelasting en KWB-doeleindes ‘n vereiste is. Die riglyne wat deur regspraak daargestel is om die inkomste-aard van aandeleverkope vas te stel, is ondersoek. Daar is bevind dat aandelewinste wat opsetlik nagejaag word en voor gewerk word, ongeag of dit deel van die bedryf van 'n besigheid is al dan nie, van ‘n inkomste-aard is en aldus belasbaar is. Die metode van identifikasie van aandele wat as handelsvoorraad verkoop word is belangrik by die berekening die inkomstebelastingwins aangesien dit gebruik word om vas te stel watter aandele verkoop is en wat die koste van die verkoopte aandele is. Daar is bevind dat die metode wat ingevolge algemeen aanvaarde rekeningkundige praktyk (AARP) toegepas is, gewoonlik ook vir inkomstebelastingdoeleindes toelaatbaar is. Artikel 9C van die Wet verskaf aan ‘n aandelehandelaar inkomstebelastingverligting met die verkoop van 'n 'kwalifiserende aandeel' deurdat die bedrag ontvang of toegeval geag word van 'n kapitale aard te wees, ongeag die inkomstebedoeling van die aandelehandelaar. Voor 1 Oktober 2007 het artikel 9B van die Wet soortgelyke verligting verskaf met die verkoop van n 'geaffekteerde aandeel’. Daar is vasgestel dat artikel 9C van die Wet 'n wyer toepassing het in vergelyking met artikel 9B van die Wet. Omrede die opbrengs ontvang met die verkoop van geaffekteerde of kwalifiserende aandele uitgesluit word van bruto inkomste, moet die vorige aankoopskostes wat voorheen ten opsigte van die aandele aangegaan en afgetrek is, by belasbare inkomste ingesluit word. Daar is bepaal dat die bedrag wat by belasbare inkomste ingesluit word, die werklike koste van die aandele is en nie die AARP openingswaarde van handelsvoorraad wat ingevolge artikel 22(2) van die Wet geëis nie. Daar is bevind dat die eerste-in-eerste-uit (EIEU) metode van identifikasie gebruik moet word om te bepaal watter geaffekteerde of kwalifiserende aandele verkoop is. Vir KWB doeleindes verloor 'n aandelehandelaar ook die geleentheid om te kan kies watter identifikasiemetode toegepas moet word. Hy of sy is verplig om die EIEU metode toe te pas in die berekening van die KWB basiskoste van die aandele. Daar word tot die gevolgtrekking gekom dat die Agtste Bylae van die Wet gewysig moet word om te bevestig dat die EIEU metode toegepas moet word vir KWB doeleindes waar artikels 9B of 9C van die Wet van toepassing is. Slegs dan is die belasbare wins van 'n aandelehandelaar in lyn is met sy of haar kontantvoordeel.
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Muñoz, Blanc Carlos. "Simulación físico-matemática de las turbulencias en los incendios de edificación. Propuesta de una nueva metodología de análisis relativa a la verificación cualitativa de las turbulencias simuladas." Doctoral thesis, Universitat Politècnica de Catalunya, 2014. http://hdl.handle.net/10803/145388.
Full textAbstract:
En la Unión Europea, y más concretamente en España, el análisis prestacional de cualquier edificio frente a la acción del fuego es aún un hecho aislado y poco habitual, a pesar de las ventajas que el mismo comporta. No obstante, incluso en aquellos países donde hace años se estudia el comportamiento estructural en situación accidental de incendio en base a los métodos prestacionales, como es el caso de Estados Unidos, el campo científico de las simulaciones computacionales basadas en la Dinámica de fluidos y en la Termodinámica está aún en lo que podríamos denominar, haciendo un símil con el crecimiento del ser humano, la fase adolescente. Mejorar en la medida de lo posible los criterios relativos
a la caracterización de un fenómeno tan importante durante el desarrollo de un fuego como es la turbulencia y disponer de una nueva metodología de análisis relativa a la verificación cualitativa de la misma permitirá avanzar con seguridad a la sociedad a medida que estas simulaciones computacionales en edificación se extiendan al terreno profesionalIn the European Union, and more specifically in Spain, the analysis of the effect of fire on any building remains an isolated and unusual fact, despite the advantages it may involve. However, even in the countries (such as the United States) where the structural behavior under a fire accidental situation has been studied under benefit methods for many years, the scientific field of computational simulations based on Fluid Dynamics and Thermodynamics remains in what could be called, in comparison to human growth, the teenage years. The improvement of the criteria used to characterize the phenomenon of turbulence and the supply of a new analysis methodology focused on its qualitative verification, so important during the development of fire, will improve society’s security, as these computational simulations are extended to the professional field.