Дисертації з теми "Turbulent shear flows"
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COHEN, JACOB. "INSTABILITIES IN TURBULENT FREE SHEAR FLOWS." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/188143.
Повний текст джерелаBuxton, Oliver R. H. "Fine scale features of turbulent shear flows." Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/9080.
Повний текст джерелаNaaseri, Masud. "Studies of complex three-dimensional turbulent flows." Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/7379.
Повний текст джерелаStrömgren, Tobias. "Model predictions of turbulent gas-particle shear flows." Doctoral thesis, KTH, Mekanik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12135.
Повний текст джерелаQC20100726
Raiford, John Phillip. "Numerical and physical modeling of turbulent shear flows." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1181669456/.
Повний текст джерелаEl-Baz, A. M. "The computational modelling of free turbulent shear flows." Thesis, University of Manchester, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509038.
Повний текст джерелаPantano-Rubino, Carlos. "Compressibility effects in turbulent nonpremixed reacting shear flows /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9981965.
Повний текст джерелаHorender, Stefan. "Experiments and simulations of particle-laden turbulent shear flows." Thesis, Imperial College London, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401859.
Повний текст джерелаLi, Li. "Modelling of dispersive transport in turbulent free shear flows." Thesis, University of the West of Scotland, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430898.
Повний текст джерелаLindgren, Björn. "Flow facility design and experimental studies of wall-bounded turbulent shear-flows." Doctoral thesis, KTH, Mechanics, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3454.
Повний текст джерелаThe presen present thesis spans a range of topics within thearea of turbulent flows, ranging from design of flow facilitiesto evaluation aluation of scaling laws and turbulence modelingdeling aspects through use of experimental data. A newwind-tunnel has been designed, constructed and evaluated at theDept. of Mechanics, KTH. Special attention was directed to thedesign of turning vanes that not only turn the flow but alsoallow for a large expansion without separation in the corners.The investigation of the flow quality confirmed that theconcept of expanding corners is feasible and may besuccessfully incorporated into low turbulence wind-tunnels. Theflow quality in the MTL wind-tunnel at the Dept. of Mechanics,KTH, was as also in investigated confirming that it still isvery good. The results are in general comparable to thosemeasured when the tunnel was as new, with the exception of thetemperature variation ariation that has decreased by a factorof 4 due to an improved cooling system.
Experimental data from high Reynolds number zeropressure-gradient turbulent layers have been investigated.These studies have primarily focused on scaling laws withe.g.confirmation of an exponential velocity defect lawin a region, about half the size of the boundary layerthickness, located outside the logarithmic overlap region. Thestreamwise velocity probability density functions in theoverlap region was found to be self-similar when scaled withthe local rms value. Flow structures in the near-wall andbuffer regions were studied ande.g. the near-wall streak spacing was confirmed to beabout 100 viscous length units although the relative influenceof the near-wall streaks on the flow was as found to decreasewith increasing Reynolds number.
The separated flow in an asymmetric plane diffuser wasdetermined using PIV and LDV. All three velocity componentswere measured in a plane along the centerline of the diffuser.Results for mean velocities, turbulence intensities andturbulence kinetic energy are presented, as well as forstreamlines and backflow coefficientcien describing theseparated region. Instantaneous velocity fields are alsopresented demonstrating the highly fluctuating flow. Resultsfor the above mentioned velocity quantities, together with theproduction of turbulence kinetic energy and the secondanisotropy inariant are also compared to data from simulationsbased on the k -wformulation with an EARSM model. The simulation datawere found to severely underestimate the size of the separationbubble.
Keywords:Fluid mechanics, wind-tunnels, asymmetricdiffuser, turbulent boundary layer, flow structures, PDFs,modeling, symmetry methods.
Nemouchi, Zoubir. "The computation of turbulent thin shear flows associated with flow around multi-element aerofoils." Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480482.
Повний текст джерелаGrosse, Sebastian. "Development of the micro-pillar shear stress sensor MPS3 for turbulent flows /." Aachen : Shaker, 2008. http://d-nb.info/991820029/04.
Повний текст джерелаZhang, Zhao. "Unstructured mesh methods for stratified turbulent flows." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/16617.
Повний текст джерелаNajafi-Yazdi, Alireza. "Large eddy simulation of sound generation by turbulent reacting and nonreacting shear flows." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=107761.
Повний текст джерелаL'objectif de cette étude est d'obtenir la meilleure compréhension des mécanismesde géneration de bruit par des jet subsoniques. Cette étude est basée sur simulations aux grandes échelles de jets réactifs et sans réactifs. Des calculs numériques employant des schéme compacts de sixiéme ordre. L'integration temporelle fut éxéciteé à l'aide de schéme Runge-Kutta de de quatrième ordre. Des schéme à faible dispersion et dissipation numérique. Un formulation intégrale basée sur les analogies acoustiques fut développées pour la prédiction du champ acoustique lointain pour les sources et observateure en mouvement dans un fluide avec vitesse uniforme. La formulation fut implémentée à l'aide d'algorithmes facilitant l'implémentation pour le traitement de données d'écoulement en haute performance utilisant des outils de simiulation à grande échelle. Les champs sonore produit par un jet turbulent non-réactif avec nombre de Mach de 0.9, et un nombre de Reynolds ReD = 400, 000 fut étudié. L'effect de la taille du maillage sur la précision de l'écoulement en champs proche et e champs sonore loin de source fut analysé. La sous-résolution de la couche de cisaillement à la sortie du jet méne à l'apparition de structures cohérentes et forte radiation qui ne sort pas physiquement réalistes. Deux mécanismes principaux de génération sonore par jets subsoniques furent identifiés. Le premier mécanisme est l'étirement et la distorsion de structures tourbillonnaires cohérentes, en particulier prés de la fin du coere potentiel. Ce mécanisme est quadripolaire, et émet principalement vers l'arriére du jet dans la direction de l'écoulement. Le seconde mécanisme semble être constitué de vibration transversale de la couche de cisaillement en réponse à la présemce de structures cohérentes dans la jet. Semblable à la radiation d'une plaque à bonds finis, la contribution de ce méchanisme est dipolaire et domine la champs sonore dans la direction transversale, perpendiculaire au jet. L'utilisation de plusieurs microjet fut investiguée pour la réduction du bruit. L'injection à l'aide de microjets précipite la transition à la turbulence, favorisent le mélange et la destrcutction de structures cohérentes de grande échelle. Un filtrage en bandes de étroites fut effectué. Ce traitement des données numériquepermet de visualiser les relations complexes entre l'écoulement et les onds sonores émises. Les résultats démontrent l'importance de modes circumférenciele, ce qui a des conséquenecs pour les modiles dits de paquets d'onde pour la preédiction du bruit du jet. Des simulation numériques d'écoulement et champs sonore d'une flame sans prémélange furent aussi éxécutées. Les simulations incluent encore une fois l'écoulement et le champ sonore associé, obtenus directement des équations de Navier Stokes compressibles. Un modèle flammelette épaissie fut proposé que donne flammes épaissies artificiellement qui peuvent être mieux résolus sur le maillage. Le bruit de combustion a des caractéristiques monopolaires aux basses fréquences. Principales sources de bruit semblent être situé dans la couche de cisaillement.
Liu, Yiou [Verfasser]. "Measuring the Wall-shear Stress for Turbulent Flows Using the Micro-Pillar Shear-Stress Sensor MPS3 / Yiou Liu." München : Verlag Dr. Hut, 2021. http://d-nb.info/1232847798/34.
Повний текст джерелаSemeraro, Onofrio. "Feedback control and modal structures in transitional shear flows." Licentiate thesis, KTH, Stabilitet, Transition, Kontroll, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-29754.
Повний текст джерелаQC 20110214
Semeraro, Onofrio. "Active Control and Modal Structures in Transitional Shear Flows." Doctoral thesis, KTH, Stabilitet, Transition, Kontroll, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-117916.
Повний текст джерелаQC 20130207
Khossousi, A. A. "A theoretical investigation of an averaged-structure eddy viscosity model applied to turbulent shear flows." Thesis, London Metropolitan University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378944.
Повний текст джерелаGroße, Sebastian [Verfasser]. "Development of the Micro-Pillar Shear-Stress Sensor MPS³ for Turbulent Flows / Sebastian Große." Aachen : Shaker, 2008. http://d-nb.info/1161308083/34.
Повний текст джерелаUmbel, Matthew R. "Prediction of Turbulent Mixing at the Interface of Density Stratified, Shear Flows Using CFD." Ft. Belvoir : Defense Technical Information Center, 1998. http://handle.dtic.mil/100.2/ADA477048.
Повний текст джерелаAlberti, Luca. "Statistical Breakdown of Numerically Simulated Shear-Free Flows." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Знайти повний текст джерелаMarstorp, Linus. "Subgrid-scale modelling for large-eddy simulation invluding scalar mixing in rotating turbulent shear flows." Licentiate thesis, KTH, Mechanics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3916.
Повний текст джерелаThe aim of the present study is to develop subgrid-scale models that are relevant for complex flows and combustion. A stochastic model based on a stochastic Smagorinsky constant with adjustable variance and time scale is proposed. The stochastic model is shown to provide for backscatter of both kinetic energy and scalar variance without causing numerical instabilities. A new subgrid-scale scalar flux model is developed using the same kind of methodology that leads to the explicit algebraic scalar flux model, EASFM, for RANS. The new model predicts the anisotropy of the subgrid-scales in a more realistic way than the eddy diffusion model. Both new models were tested in rotating homogeneous shear flow with a passive scalar. Rogallo’s method of moving the frame with the mean flow to enable periodic boundary conditions was used to simulate homogeneous shear flow.
Marstorp, Linus. "Subgrid-scale modelling for large-eddy simulation including scalar mixing in rotating turbulent shear flows." Licentiate thesis, KTH, Mekanik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3916.
Повний текст джерелаQC 20101119
Helvey, Jacob. "Experimental Investigation of Wall Shear Stress Modifications due to Turbulent Flow over an Ablative Thermal Protection System Analog Surface." UKnowledge, 2015. http://uknowledge.uky.edu/me_etds/57.
Повний текст джерелаCuthbertson, Alan J. S. "The motion of fine sand particles in turbulent open channel shear flows over porous bed conditions." Thesis, University of Glasgow, 2001. http://theses.gla.ac.uk/2489/.
Повний текст джерелаRolling, August Jameson. "Design of Gages for Direct Skin Friction Measurements in Complex Turbulent Flows with Shock Impingement Compensation." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/28093.
Повний текст джерелаPh. D.
Shirai, Katsuaki [Verfasser]. "Investigation and Application of Laser Doppler Velocity Profile Sensors toward Measurements of Turbulent Shear Flows / Katsuaki Shirai." Aachen : Shaker, 2010. http://d-nb.info/1122546777/34.
Повний текст джерелаBagheri, Shervin. "Analysis and control of transitional shear flows using global modes." Doctoral thesis, Stockholm : Department of Mechanics, Royal Institute of Technology, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11894.
Повний текст джерелаHyensjö, Marko. "Fibre Orientation Modelling Applied to Contracting Flows Related to Papermaking." Doctoral thesis, KTH, Mekanik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4762.
Повний текст джерелаQC 20100812
Louis, Stephen. "Continuer à irriguer quand les lacs-réservoirs de barrage souffrent de taux de sédimentation sévères - Recommandations d'amélioration de la gestion du principal canal d'irrigation alimenté par l'ouvrage répartiteur de Canneau (Haïti)." Doctoral thesis, Universite Libre de Bruxelles, 2019. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/288808.
Повний текст джерелаDoctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished
Scharnowski, Sven [Verfasser], Christian J. [Akademischer Betreuer] Kähler, Fulvio [Akademischer Betreuer] Scarano, and Christoph [Akademischer Betreuer] Garbe. "Investigation of turbulent shear flows with high resolution PIV methods / Sven Scharnowski. Universität der Bundeswehr München, Fakultät für Luft- und Raumfahrttechnik. Gutachter: Christian J Kähler ; Fulvio Scarano ; Christoph Garbe. Betreuer: Christian J Kähler." Neubiberg : Universitätsbibliothek der Universität der Bundeswehr München, 2014. http://d-nb.info/1049833686/34.
Повний текст джерелаHuret, Thomas. "Génération en soufflerie d'écoulements cisaillés représentatifs des écoulements environnementaux de couches limites atmosphériques par des dispositifs passifs." Electronic Thesis or Diss., Centrale Lille Institut, 2024. http://www.theses.fr/2024CLIL0011.
Повний текст джерелаIn the field of wind engineering, a common practice for both research and industrial applications involving the generation of a neutral atmospheric boundary layer (ABL) in a wind tunnel consists in associating a roughness fetch with an upstream array of “spires”. This passive method enables to tailor the mean velocity profile on the basis of quantitative guidelines. At the expense of a further time-consuming trial-and-error design process, these devices can be adjusted to generate representative turbulent intensity profiles.In parallel, the downstream evolution of regular and fractal grid-generated turbulence has been recently shown to scale with a wake-interaction model which can be used to predict basic properties of downstream turbulence profiles in case of zero mean shear. If this scaling law were to apply to grid-generated shear flow, it would enable the independent tailoring of turbulent intensity and mean velocity profiles without trial-and-error, contrary to previous spires devices. In order to investigate these ideas experimentally, our work makes use of Multiscale Inhomogeneous Grids (MIG), a new type of passive device defined to vary the turbulence scaling parameters with altitude, while enabling a tailoring of the mean velocity profile. In particular, it is shown that "spires" represent a specific case of "continuous" MIG grids.A general MIG design algorithm is developed for the generation of a prescribed mean flow profile. It is experimentally validated for the design of both discrete MIG grids and spires aiming to generate full-depth and part-depth neutral atmospheric boundary layer configurations. The devices are studied over both smooth and rough walls in the SCL-PIV wind tunnel of ONERA Lille using both Hot-Wire Anemometry (HWA) and stereo Particle Image Velocimetry (S-PIV). This validation process reveals the existence of a defective grid regime for specific local geometric configurations of MIG grids. A set of criteria on local geometric parameters (i.e. local obstruction and local mesh aspect ratio) is suggested to avoid this defective grid regime.The turbulence intensity decay downstream of the designed MIG grids is then studied by scaling its streamwise profile measured downstream of each horizontal grid level by the corresponding wake-interaction parameters for zero shear grid flows. A very good collapse of the turbulence decay is observed for all discrete MIG grids, with however a slight remnant effect of the local mean shear. Moreover, a collapse of spires-generated curves is also observed over a specific range of altitudes, but on a different collapse curve than for discrete MIG grids.An attempt to take into account both the remaining effect of mean shear on the turbulence decay and the observed collapse discrepancy between discrete and continuous MIG grids leads to the development of a simplified Turbulent Kinetic Energy (TKE) model. Several terms of this model remain to be closed in order to provide an a priori prediction. Successful closing empirical models are developed for both Reynolds stress and integral length scales, but not for the turbulent dissipation rate due to a lack of experimental data.The experimental investigation of the different hypotheses of the TKE model surprisingly revealed complex mean shear and streamwise vorticity patterns persisting far downstream of both spires and discrete MIG grids. These diverse and complex structures, originating from the near-wake flows around the upstream devices, are acknowledged as the main cause of discrepancy between spires and MIG grids. Tailoring turbulence intensity for ABL generation in wind tunnel appears to require an understanding and a modeling of this near-wake complexity
Babarutsi, Sofia. "Modelling quasi-two-dimensional turbulent shear flow." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70223.
Повний текст джерелаAlathur, Srinivasan Prem Anand. "Deep Learning models for turbulent shear flow." Thesis, KTH, Numerisk analys, NA, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-229416.
Повний текст джерелаDjupa neuronät som är tränade med rum-tids utveckling av ett dynamiskt system kan betraktas som ett empiriskt alternativ till konventionella modeller som använder differentialekvationer. I denna avhandling konstruerar vi sådana djupinlärningsmodeller för att modellera en förenklad lågdimensionell representation av turbulensfysiken. Träningsdata för neuronäten erhålls från en 9-dimensionell modell (Moehlis, Faisst och Eckhardt [29]) för olika Fourier-moder i ett skärskikt. Dessa moder har ändamålsenligt valts för att avbilda de turbulenta strukturerna i regionen nära väggen. Amplitudernas tidsserier för dessa moder beskriver fullständigt flödesutvecklingen, och tränade djupinlärningsmodeller används för att förutsäga dessa tidsserier baserat på en kort indatasekvens. Två fundamentalt olika neuronätsarkitekturer, nämligen flerlagerperceptroner (MLP) och långa närminnesnätverk (LSTM), jämförs kvantitativt i denna avhandling. Utvärderingen av dessa arkitekturer är baserad på (i) hur väl deras förutsägelser presterar jämfört med den 9-dimensionella modellen, (ii) förutsägelsernas förmåga att avbilda turbulensstrukturerna nära väggar och (iii) den statistiska överensstämmelsen mellan nätverkets förutsägelser och testdatan. Det visas att LSTM gör förutsägelser med ett fel på ungefär fyra storleksordningar lägre än för MLP. Vidare, är strömningsfälten som är konstruerade från LSTM-förutsägelser anmärkningsvärt noggranna i deras statistiska beteende. I synnerhet uppmättes avvikelser mellan de sanna- och förutsagda värdena för det genomsnittliga flödet till 0; 45 %, och för de strömvisa hastighetsfluktionerna till 2; 49 %.
Campana, Lorenzo. "Modélisation stochastique de particules non sphériques en turbulence." Thesis, Université Côte d'Azur, 2022. http://www.theses.fr/2022COAZ4019.
Повний текст джерелаThe motion of small non- spherical particles suspended in a turbulent flow is relevant for a large variety of natural and industrial applications such as aerosol dynamics in respiration, red blood cells motion, plankton dynamics, ice in clouds, combustion, to name a few. Anisotropic particles react on turbulent flows in complex ways, which depend on a wide range of parameters (shape, inertia, fluid shear). Inertia-free particles, with size smaller than the Kolmogorov length, follow the fluid motion with an orientation generally defined by the local turbulent velocity gradient. Therefore, this thesis is focused on the dynamics of these objects in turbulence exploiting stochastic Lagrangian methods. The development of a model that can be used as predictive tool in industrial computational fluid dynamics (CFD) is highly valuable for practical applications in engineering. Models that reach an acceptable compromise between simplicity and accuracy are needed for progressing in the field of medical, environmental and industrial processes. The formulation of a stochastic orientation model is studied in two-dimensional turbulent flow with homogeneous shear, where results are compared with direct numerical simulations (DNS). Finding analytical results, scrutinising the effect of the anisotropies when they are included in the model, and extending the notion of rotational dynamics in the stochastic framework, are subjects addressed in our work. Analytical results give a reasonable qualitative response, even if the diffusion model is not designed to reproduce the non-Gaussian features of the DNS experiments. The extension to the three-dimensional case showed that the implementation of efficient numerical schemes in 3D models is far from straightforward. The introduction of a numerical scheme with the capability to preserve the dynamics at reasonable computational costs has been devised and the convergence analysed. A scheme of splitting decomposition of the stochastic differential equations (SDE) has been developed to overcome the typical instability problems of the Euler–Maruyama method, obtaining a mean-square convergence of order 1/2 and a weakly convergence of order 1, as expected. Finally, model and numerical scheme have been implemented in an industrial CFD code (Code_Saturne) and used to study the orientational and rotational behaviour of anisotropic inertia-free particles in an applicative prototype of inhomogeneous turbulence, i.e. a turbulent channel flow. This real application has faced two issues of the modelling: the numerical implementation in an industrial code, and whether and to which extent the model is able to reproduce the DNS experiments. The stochastic Lagrangian model for the orientation in the CFD code reproduces with some limits the orientation and rotation statistics of the DNS. The results of this study allows to predict the orientation and rotation of aspherical particles, giving new insight into the prediction of large scale motions both, in two-dimensional space, of interest for geophysical flows, and in three-dimensional industrial applications
Schmiegel, Armin. "Transition to turbulence in linearly stable shear flows." [S.l. : s.n.], 1999. http://archiv.ub.uni-marburg.de/diss/z2000/0062.
Повний текст джерелаLefauve, Adrien Sébastien Paul. "Waves and turbulence in sustained stratified shear flows." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/277352.
Повний текст джерелаEtebari, Ali. "Wall shear measurements in arterial flows." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/27326.
Повний текст джерелаPh. D.
Ciochetto, David S. "Analysis of Three Dimensional Turbulent Shear Flow Experiments with Respect to Algebraic Modeling Parameters." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36808.
Повний текст джерелаMaster of Science
Lazeroms, Werner. "Explicit algebraic turbulence modelling in buoyancy-affected shear flows." Licentiate thesis, KTH, Turbulens, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-122468.
Повний текст джерелаQC 20130530
Zhu, Ying. "Modelling and calculation for shear-driven rotating turbulence, with multiscale and directional approach." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEC002/document.
Повний текст джерелаStability and turbulence in rotating shear flows is essential in many contexts ranging from engineering—as in e.g. turbomachinery or hydraulic energy production—to geophysics and astrophysics. Apart from inhomogeneous effects which we discard in the present study, these flows are complex because they involve an anisotropic dynamics which is difficult to represent at the level of one-point statistics. In this context, the properties of these flows, such as scale-by-scale anisotropy or turbulent cascade can be studied via two-point statistical models of Homogeneous Anisotropic Turbulence (HAT), in which the distorting mean flow is represented by uniform mean velocity and density gradients, and by body forces as the Coriolis one. The context of HAT can be relevant for flows in a plane channel with spanwise rotation, or for a Taylor-Couette flow. We propose a new model for predicting the dynamics of homogeneous sheared rotating turbulence. The model separates linear distortion effects from nonlinear turbulent dynamics, so that each contribution can be treated with an adapted model. Our model deals with equations governing the spectral tensor of two-point second-order velocity correlations, and is developed for arbitrary mean velocity gradients with or with- out system rotation. The direct linear effect of mean gradients is exact in our model, whereas nonlinear effects come from two-point third-order correlations which are closed by an anisotropic EDQNM model. In the closure, the anisotropy is restricted to an expansion in terms of low-degree angular harmonics (Mons et al., 2016). The present model has been validated in the linear regime, by comparison to the accurate solution of viscous Rapid Distortion Theory (vRDT), in several cases, stabilizing, destabilizing or neutral. In contrast with pseudo-spectral DNS adapted to shear flow by Rogallo (1981) in en- gineering and by Lesur & Longaretti (2005) in astrophysics, the advection operator is not solved by following characteristic lines in spectral or physical space, but by an original high- order finite-difference scheme for calculating derivatives ∂ i with respect to the wave vector k. One thus avoids mesh deformation and remeshing, thus one can easily extract angular ii harmonics at any time since physical or spectral space are not distorted. With this new approach, we are able to improve the prediction of the previous model by Mons et al. (2016), in which the linear resolution is questioned at large time, especially in the case without rotation. The proposed new model is versatile since it is implemented for several cases of mean velocity gradients consistent with the homogeneity approximation. Validations have been done for several cases of plane deformations. In the case of sheared turbulence, whose modelling resists most one-point approaches and even the two-point model by Mons, we propose an adaptation of our two-point model in a new hybrid model, in which return-to- isotropy is explicitly introduced in the guise of Weinstock (2013)’s model. Predictions of the new hybrid model are extremely good
Ramesh, Chandra D. S. "Turbulent Mixed Convection." Thesis, Indian Institute of Science, 2000. https://etd.iisc.ac.in/handle/2005/236.
Повний текст джерелаRamesh, Chandra D. S. "Turbulent Mixed Convection." Thesis, Indian Institute of Science, 2000. http://hdl.handle.net/2005/236.
Повний текст джерелаSreedhar, Madhu K. "Large eddy simulation of turbulent vortices and mixing layers." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-163324/.
Повний текст джерелаShen, Peiquing. "Numerical study of fluid particle dispersion in homogeneous turbulent shear flow." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/12486.
Повний текст джерелаJohnstone, Henry Webb 1956. "CONFINED JET-INDUCED MIXING AT A DENSITY INTERFACE (TURBULENT, SHEAR FLOW)." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/292003.
Повний текст джерелаBaum, Bryan Alan. "The extension of rapid distortion theory to stratified shear flows." Diss., Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25971.
Повний текст джерелаMonokrousos, Antonios. "Optimisation and control of shear flows." Doctoral thesis, KTH, Stabilitet, Transition, Kontroll, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-33771.
Повний текст джерелаQC 20110518
Deshpande, Kiran B. "Studies On Phase Inversion." Thesis, Indian Institute of Science, 2001. https://etd.iisc.ac.in/handle/2005/285.
Повний текст джерелаDeshpande, Kiran B. "Studies On Phase Inversion." Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/285.
Повний текст джерела