Dissertations / Theses on the topic 'CFD numerical simulation'
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Choi, Hong Fei. "Numerical simulation of atrium fire using two CFD tools." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1694321.
Karlsson, Karl. "Numerical Simulation of Sabot Discard Projectile." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-79248.
Crozon, Clément. "Coupling flight mechanics and CFD : numerical simulation of shipborne rotors." Thesis, University of Liverpool, 2015. http://livrepository.liverpool.ac.uk/2030079/.
Cox-Stouffer, Susan K. Jr. "Numerical Simulation of Injection and Mixing in Supersonic Flow." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/29628.
Ph. D.
Li, Ning. "Comparison between three different CFD software and numerical simulation of an ambulance hall." Thesis, KTH, Energiteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-160938.
El, Mellas Ismail. "Numerical simulation of wax deposition in pipelines." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2020.
Henson, Jonathan Charles. "Numerical simulation of spark ignition engines with special emphasis on radiative heat transfer." Thesis, Loughborough University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297589.
Hayati, Abolfazl. "NUMERICAL STUDY OF 2D PARTICLE FLOW IN A DUCT." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-13324.
Reasor, Jr Daniel A. "NUMERICAL SIMULATION OF TWO FLOW CONTROL APPROACHES FOR LOW REYNOLDS NUMBER APPLICATIONS." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/461.
Kara, Sibel. "Numerical simulation of flow in open-channels with hydraulic structures." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/54033.
Stenger, Douglas. "Three-Dimensional Numerical Simulation of Film Cooling on a Turbine Blade Leading-Edge Model." University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1236053109.
Zhai, Qiang. "A NUMERICAL STUDY OF A HEAT EXCHANGER SYSTEM WITH A BYPASS VALVE." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461252171.
Cadafalch, Rabasa Jordi. "Numerical Simulation of Turbulent Flows. Multiblock Techniques. Verification and Experimental Validation." Doctoral thesis, Universitat Politècnica de Catalunya, 2002. http://hdl.handle.net/10803/6681.
The thesis comprises six main chapters written in a paper format. Two of them have already been published in international journals, one in the proceedings of a Spanish conference and two in proceedings of international conferences on Computational Fluid Dynamics and heat transfer. The last chapter has recently been submitted for publication to an international journal. Therefore, all the chapters are written so as to be self-contained, complete and concise. As a consequence, some contents of the chapters such those describing the governing equations, or the verification procedure used to assess the credibility of the numerical solutions, are repeated in several of them. Furthermore, as only minor changes have been introduced in the chapters respect to the original papers, each of them reflects the know-how of the CTTC (Heat and Mass Transfer Technological Centre were the research has been carried out) when they were published.
Papers presented in chapters 1 and 2 deal with turbulence modelling. A general overview is given on the formulation and numerical techniques of the different levels of turbulence modelling: Direct Numerical Simulation (DNS), Large Eddy Simulation (LES) and Reynolds Averaged Navier-Stokes Simulation (RANS). Main attention is focussed on the eddy viscosity two-equation RANS models. Their formulation is presented in more detail, and numerical solutions of the most extended. Benchmark problems on turbulence modelling are given compared to the available experimental data.
Chapters 3 and 4 focus on the use of the multiblock method (domain decomposition method), as a numerical technique that combined with the parallel computing may allow reducing the demanding computational time and memory (high performance computing). The multiblock approach used is based on the conservation of all the physical quantities (fully conservative method) and on an explicit information exchange between the different blocks of the domain. The goal of the work presented in these two chapters is to verify that such a multiblock approach does not introduce additional uncertainty in the numerical solutions.
Chapter 5 presents a tool that has been developed at the CTTC for the verification of finite volume computations. In fact, this tool is also partially used and described in the results presented in the previous chapters. Here, it is described and discussed in detail and it is applied to a set of different CFD and heat transfer problems in two and three dimensions, with free and forced convection, with reactive and non-reactive flows and with laminar and turbulent flows.
The last chapter shows a complete study for the development of a credible heat transfer relation for the heat evacuated from a ventilation channel. Such study comprises all the different steps that have to be accomplished so as to develop credible and applicable results in mechanical engineering. It comprises a description of the mathematical model to represent the physical phenomena in the channel, the numerical model to solve the set of coupled differential equations of the mathematical model, the construction and testing of an ad-hoc experimental set-up, and a verification and validation (V&V) test that guarantees that the numerical solution is an accurate enough approximation of the mathematical model (verification), and that it properly predicts the reality (validation).
Petersson, Sven. "Simulation of Phase Contrast MRI Measurements from Numerical Flow Data." Thesis, Linköping University, Department of Biomedical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-14871.
Phase-contrast magnetic resonance imaging (PC-MRI) is a powerful tool for measuring blood flow and has a wide range of cardiovascular applications. Simulation of PC-MRI from numerical flow data would be useful for addressing the data quality of PC-MRI measurements and to study and understand different artifacts. It would also make it possible to optimize imaging parameters prior to the PC-MRI measurements and to evaluate different methods for measuring wall shear stress.
Based on previous studies a PC-MRI simulation tool was developed. An Eulerian-Lagrangian approach was used to solve the problem. Computational fluid dynamics (CFD) data calculated on a fix structured mesh (Eulerian point of view) were used as input. From the CFD data spin particle trajectories were computed. The magnetization of the spin particle is then evaluated as the particle travels along its trajectory (Lagrangian point of view).
The simulated PC-MRI data were evaluated by comparison with PC-MRI measurements on an in vitro phantom. Results indicate that the PC-MRI simulation tool functions well. However, further development is required to include some of the artifacts. Decreasing the computation time will make more accurate and powerful simulations possible. Several suggestions for improvements are presented in this report.
Kapa, Lilla. "Numerical prediction of noise production and propagation." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209828.
nearfield, a linear set of propagation equations may be considered (LEE). For such problems, the following simulation methodology is proposed:
1. Incompressible/compressible LES simulation in the source region.
2. Linearized Euler Equations to propagate the noise through the nonlinear mean flow.
3. Kirchhoff method in the farfield, if necessary.
This thesis deals with the second item of this system (LEE), including interfacing with the other two steps.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
Donnelly, David Johnson. "Numerical Simulation of Surface Effect Ship Air Cushion and Free Surface Interaction." Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/35326.
Master of Science
BOIGUES, MUNOZ CARLOS. "Computational Simulation of Solid Oxide Fuel Cells – Integrating numerical and experimental approaches." Doctoral thesis, Università Politecnica delle Marche, 2015. http://hdl.handle.net/11566/242989.
Solid oxide fuel cell (SOFC) is a promising electrochemical technology that can produce electrical and thermal power with outstanding efficiencies, however, a more profound understanding of the physicochemical processes occurring within the cell is necessary to overcome most of the degradation issues currently impeding the maturity of the technology. A systematic synergetic approach between experimental measurements, the use of novel analysis tools and techniques – with special attention to the deconvolution of electrochemical impedance spectroscopy (EIS) spectra by means of the distribution of relaxation times (DRT) method – and modelling theory has proved to be instrumental for the estimation of parameters describing the microstructural and electrochemical properties of two types of planar anode-supported SOFCs, one designed to operate at intermediate temperatures (750ºC) and the other at low temperatures (650ºC). A comprehensive macro-scale computational fluid dynamics (CFD) model of the tested samples incorporating the aforementioned parameters has been validated by confronting the simulated polarization curves with the experimental ones. This model has demonstrated to be a compelling tool to optimize the microstructure of the cells whilst establishing the bases to monitor and analyse the effects of potential degradation phenomena in the cell and predict the electrical output of the cell in the long run under pre-determined operating conditions. Additionally, a CFD model of a tubular-type cell comprised in the power module (i.e. SOFC stack) of a characterised 500Wel power generator has enabled to appreciate how a singular element of the stack behaves under nearly realistic operating conditions.
Ibarra, Medina Juansethi Ramses. "Development and application of a CFD model of laser metal deposition." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/development-and-application-of-a-cfd-model-of-laser-metal-deposition(d74829d8-c4b9-40f1-b80f-cbdc456ffaf5).html.
Crialesi, Esposito Marco. "Analysis of primary atomization in sprays using Direct Numerical Simulation." Doctoral thesis, Universitat Politècnica de València, 2019. http://hdl.handle.net/10251/133975.
[CAT] La comprensió dels fenòmens físics que succeïxen en la regió densa (també coneguda com a camp pròxim) durant l'atomització dels sprays ha sigut una de les majors incògnites a l'hora d'estudiar les seues aplicacions. En el sector industrial, el rang d'interés comprén des de toveres en aplicacions propulsives a sprays en aplicacions mèdiques, agrícoles o culinàries. Esta evident falta de coneixement obliga a realitzar simplificacions en la modelització, provocant resultats poc precisos i la necessitat de grans caracteritzacions experimentals en la fase de disseny. D'esta manera, els processos de ruptura del spray i atomització primària es consideren problemes físics fonamentals, la complexitat dels quals ve donada com resultat d'un flux multifàsic en un règim altament turbulent, originant escenaris caòtics. L'anàlisi d'este problema és extremadament complex a causa de l'absència substancial de teories validades dels fenòmens físics involucrats com són la turbulència i l'atomització. A més, la combinació de la naturalesa multifàsica del flux i el seu comportament turbulent resulten en una gran dificultat per a afrontar el problema. Durant els últims 10 anys les tècniques experimentals han sigut finalment capaces de visualitzar la regió densa, però la confiança, anàlisi i efectivitat dels experiments en esta regió del spray encara requerix de millores substancials. En este context, esta tesi tracta de contribuir en l'enteniment d'estos processos físics i de proporcionar ferramentes d'anàlisi per a estos fluxos tan complexos. Per a això, per mitjà de Direct Numerical Simulations s'ha afrontat el problema resolent les escales de moviment més menudes, al mateix temps que es capturen totes les escales de turbulència i esdeveniments de ruptura. Un dels objectius de la tesi ha sigut avaluar la influència que les condicions de contorn del flux entrant tenen en l'atomització primària i en el comportament turbulent del spray. Per a això, s'han empleat dos condicions de contorn diferents. En primer lloc s'ha empleat una condició de contorn sintètica per a produir turbulència homogènia a l'entrada, simulant el comportament de la tovera. Una de les característiques més interessants d'este mètod és la possibilitat de retocar els paràmetres dins de l'algoritme. En particular, l'escala de longitud integral s'ha variat per a avaluar la influència de les estructures mes grans de la tovera en l'atomització primària. L'anàlisi de la condició de contorn sintètica també ha permés el disseny òptim de simulacions de les quals s'han derivat estadístiques turbulentes significatives. En este escenari, s'han dut a terme estudis més profunds sobre la influència de propietats de les estructures turbulentes com l'homogeneïtat i l'anisotropia tant en l'espectre dels fluxos com en les estadístiques de les gotes. Per a tal fi, s'han desenrotllat metodologies noves per a computar l'anàlisi espectral i l'estadística de les gotes. Entre els resultats d'esta anàlisi destaca la independència de la condició de contorn d'entrada en les estadístiques de les gotes, mentres que d'altra banda, es recalca que les característiques turbulentes desenrotllades en l'interior de la tovera afecten a la quantitat total de massa atomitzada. Estes consideracions es troben recolzades per l'anàlisi espectral realitzat, per mitjà del qual es conclou que la turbulència multifásica compartix el comportament universal descrit per les teories de Kolmogorov.
[EN] The understanding of the physical phenomena occurring in the dense region (also known as near field) of atomizing sprays has been long seen as one of the biggest unknown when studying sprays applications. The industrial range of interest goes from nozzles in combustion and propulsion applications to medical sprays, agricultural and food process applications. This substantial lack of knowledge is responsible for some important simplification in modeling, that often result to be inaccurate or simply partial, leading to the evident need of large experimental characterization during the design phase. In fact, the spray breakup and primary atomization processes are indeed fundamental problems of physics, which complexity results from the combination of a multiphase flow in a highly turbulent regime that leads to chaotic scenarios. The analysis of this problem is extremely problematic, due to a substantial lack of definitive theories about the physical phenomena involved, namely turbulence and atomization. Furthermore, the combination of the multiphase nature of the flow and its turbulent behavior makes substantially difficult to address the problem. Only within the last 10 years, experimental techniques have been capable of visualizing the dense region, but the experiments reliability, analysis and effectiveness in this region still requires vast improvements. In this scenario, this thesis aims to contribute in the understanding of these physical process and to provide analysis tools for these complex flows. In order to do so, Direct Numerical Simulations have been used for addressing the problem at its smallest scale of motion, while reliably capturing all turbulence scales and breakup events. The multiphase nature of the flow is accounted for by using the Volume of Fluid method. One of the goal of the thesis was to assess the influence of the inflow boundary conditions on the primary atomization and on the spray's turbulence behavior. In order to do so, two different boundary conditions were used. In a first place, a synthetic inflow boundary condition was used in order to produce a homogeneous turbulence inflow, simulating the nozzle behavior. One of the interesting features of this method was the possibility of tweaking the parameters within the algorithm. In particular, the integral length scale was varied in order to assess the influence of nozzle larger turbulent structures on the primary atomization. The analysis on the synthetic boundary condition also allowed to optimally design simulations from which derive meaningful turbulence statistics. On this framework, further studies were carried over on the influence of turbulent structures properties, namely homogeneity and anisotropy, on both the flows spectra and droplets statistics. In order to achieve this goal, novel procedures for both computing the flow spectra and analyzing droplets were developed and are carefully addressed in the thesis. The results of the analysis highlight the independence of droplets statistics from the inflow boundary condition, while, on the other hand, remarking how the total quantity of atomized mass is significantly affected by the turbulence features developed within the nozzle. This considerations are supported by the spectrum analysis performed, which also highlighted how multiphase turbulence shares the universal features described in Kolmogorov theories.
Crialesi Esposito, M. (2019). Analysis of primary atomization in sprays using Direct Numerical Simulation [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/133975
TESIS
Mason, Kevin Richard. "Development of numerical schemes to improve the efficiency of CFD simulation of high speed viscous aerodynamic flows." Thesis, Swansea University, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.678434.
Elfahem, Rim. "Modélisation numérique CFD du comportement thermique cutané humain en Cryothérapie Corps Entier à -110°C." Electronic Thesis or Diss., Reims, 2023. http://www.theses.fr/2023REIMS023.
This thesis presents the CFD modelling of human cutaneous thermal behaviour in whole-body cryotherapy (WBC), a cold treatment that involves exposing the entire body to very low temperatures (-110°C) for 3 to 4 minutes. The objective is to optimize cryotherapy protocols that are specific and tailored to everyone. Experimental approaches (cutaneoustemperature mapping by infrared thermography) and measurements of actual temperatures in the main cryotherapy chamber are carried out to provide input boundary conditions for simulations, on the one hand, and to validate numerical results on the other hand. A mathematical model has been developed to predict the cooling of skin temperature in different body areas during a whole-body cryotherapy (WBC) session for various populations and morphotypes.Numerical simulations were conducted to determine the thermo-aerodynamic behaviour of both the empty and occupied cryotherapy chamber. These simulations revealed that the presence of a person disrupts the thermal and airflow fields within the chamber during the WBC session, leading to an increase in chamber temperature due to heat dissipation bythe person. This phenomenon becomes more pronounced as the number of subjects increases. Further simulations were carried out to investigate the cutaneous cooling kinetics for different morphotypes during WBC sessions. The numericalmodels were validated against experimental results, demonstrating a good agreement between the two results
Eggenspieler, Gilles. "Numerical simulation of pollutant emission and flame extinction in lean premixed systems." Diss., Available online, Georgia Institute of Technology, 2005, 2005. http://etd.gatech.edu/theses/available/etd-06222005-132512/.
Yedidia Neumeier, Committee Member ; Jerry Seitzman, Committee Member ; Fotis Sotiropoulos, Committee Member ; Tim Lieuwen, Committee Member ; suresh menon, Committee Chair.
Wang, Bao. "Numerical Simulation of Detonation Initiation by the Space-Time Conservation Element and Solution Element Method." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1293461692.
Berrini, Elisa. "Modèle géométrique déformable pour la simulation et l’optimisation automatique de forme." Thesis, Université Côte d'Azur (ComUE), 2017. http://www.theses.fr/2017AZUR4036/document.
The precise control of geometric models plays an important role in many domains. For shape optimisation in CFD, the choice of control parameters and the way to deform a shape are critical. In this thesis, we propose a new approach to shape deformation for parametric modellers with the purpose of being integrated into an automatic shape optimisation loop with a CFD solver. Our methodology is based on a twofold parameterisation: geometrical and architectural. The geometrical approach consist of a skeleton-based representation of object. The skeleton is made of a family of B-Spline curves, called generating curve and section curves. The skeleton is parametrised with an architectural approach: meaningful design parameters are chosen on the studied object. Thus, instead of using the control points of a classical B-spline representation, we control the geometry in terms of architectural parameters. This reduce the number of degrees of freedom and maintain a high level description of shapes. We ensure to generate valid shapes with a strong shape consistency control based on architectural considerations. Deformations of the geometry are performed by solving optimisation problems on the skeleton. Finally, a surface reconstruction method is proposed to evaluate the shape’s performances with CFD solvers. We illustrate the parametric modeller capabilities on three problems, performed with an automatic shape optimisation loop: the wind section of an plane (airfoil), the foil of an AC45 racing sail boat and the bulbous bow of a fishing trawler
Bayer, Ozgur. "Simulation Of Refrigerated Space With Radiation." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/3/12610454/index.pdf.
Kullab, Alaa. "Desalination using Membrane Distillation : Experimental and Numerical Study." Doctoral thesis, KTH, Kraft- och värmeteknologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-44405.
QC 20111021
Chebli, Rezki. "Simulation 2D et 3D des écoulements cavitants : développement d'un algorithme original dans Code_Saturne et étude de l'influence de la modélisation de la turbulence." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0040/document.
Cavitation is one of the most demanding physical phenomena influencing the performance of hydraulic machines. It is therefore important to predict correctly its inception and development, in order to quantify the performance drop it induces, and also to characterize the resulting flow instabilities. The aim of this work is to develop an unsteady 3D algorithm for the numerical simulation of cavitation in an industrial CFD solver « Code_saturne ». It is based on a fractional step method and preserves the minimum/maximum principle of the void fraction. An implicit solver, based on a transport equation of the void fraction coupled with the Navier-Stokes equations is proposed. A specific numerical treatment of the cavitation source terms provides physical values of the void fraction (between 0 and 1) without including any artificial numerical limitation. The influence of RANS turbulence models on the simulation of cavitation on 2D geometries (Venturi and Hydrofoil) is then studied. It confirms the capability of the two-equation eddy viscosity models, k-epsilon and k-omega-SST, with the modification proposed by Reboud et al. (1998) to reproduce the main features of the unsteady sheet cavity behavior. The second order model RSM-SSG, based on the Reynolds stress transport, appears able to reproduce the highly unsteady flow behavior without including any arbitrary modification. The three-dimensional effects involved in the instability mechanisms are also analyzed. This work allows us to achieve a numerical tool, validated on complex configurations of cavitating flows, to improve the understanding of the physical mechanisms that control the three-dimensional unsteady effects involved in the mechanisms of instability
Laugwitz, Alexander. "Detailed analyses and numerical modeling of a new multi-staged fluidized-bed gasifier." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2018. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-230465.
Mebrouk, Ridha. "Étude paramétrique des échanges convectifs turbulents dans les configurations d’intérêt pratique." Thesis, Reims, 2017. http://www.theses.fr/2017REIMS036/document.
This thesis presents the results of two studies: the first concerns natural turbulent convection in a rectangular cavity heated from the bottom wall and filled with a nanofluid and the second relates to the investigation of conjugate heat transfer in a fin-and-tube heat exchanger.The cavity of the first study is tall and has a heat source embedded on its bottom wall, while its left, right and top walls are maintained at a relatively low temperature. The working fluid is a water based nanofluid having three nanoparticle types: alumina, copper and copper oxide. The influence of pertinent parameters such as the Rayleigh number, the type of nanofluid and solid volume fraction of nanoparticles on the cooling performance is studied. Steady forms of twodimensional Reynolds-Averaged-Navier-Stokes equations and conservation equations of mass and energy, coupled with the Boussinesq approximation, are solved by the volume control based on the discretisation method employing the SIMPLE algorithm for pressure-velocity coupling. Turbulence is modeled by using the standard k-epsilon model. The Rayleigh number, Ra, is varied from 2.49xE09 to 2.49xE11. The volume fractions of nanoparticles where varied too. Stream lines, isotherms, velocity profiles and temperature profiles are presented for various combinations of Ra, the type of nanofluid and solid volume fraction of nanoparticles. The results are reported in the form of average Nusselt number on the heated wall. It is shown that for all values of Ra, the average heat transfer rate from the heat source increases almost linearly and monotonically as the solid volume fraction increases. Finally the average heat transfer rate takes on values that decrease according to the ordering Cu, CuO and Al2O3.In the second study We determined the heat transfer and friction characteristics of a realistic fin-and-tube heat exchanger. The computations assume steady-state heat transfer and fluid flow. Nusselt number and friction factor characteristics of the heat exchanger are presented for various values of Reynolds numbers. The energy conservation and the heat conduction equations in 3 dimensions have been solved in the fluid and the solid respectivelyalong with the mass and momentum conservation equations in order to determine these characteristics. Both laminar and turbulent flow regimes are considered. The effect of turbulence modeling was investigated using three different models (the one equation Spalart-Allmaras turbulence model, the standard k-epsilon; model and the RSM model). The computations allowed the determination of the dynamic and thermal fields. Model validation was carried out by comparing the calculated friction factor f and Colburn j-factor to experimental results found in the literature. The plotted results showed a qualitatively good agreement between numerical results and experimental data. The results obtained also showed that the simplest of the three turbulence models tested(i.e. Spalart-Allmaras) gives the closest values to the experimental data
Nabati, Hamid. "Optimal Pin Fin Heat Exchanger Surface." Licentiate thesis, Mälardalen University, School of Sustainable Development of Society and Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-1032.
This research presents the results of numerical study of heat transfer and pressure drop in a heat exchanger that is designed with different shape pin fins. The heat exchanger used for this research consists of a rectangular duct fitted with different shape pin fins, and is heated from the lower plate. The pin shape and the compact heat exchanger (CHE) configuration were numerically studied to maximize the heat transfer and minimize the pressure drop across the heat exchanger. A three dimensional finite volume based numerical model using FLUENT© was used to analyze the heat transfer characteristics of various pin fin heat exchangers. The simulation applied to estimate the heat transfer coefficient and pressure drop for a wide range of Reynolds numbers with different pin fins. Circular pin configuration variations included changes in pin spacing, axial pitch and pin height ratio. Rectangular and drop-shaped pin variations also included changes in length and aspect ratio. Correlations for Nusselt number and friction factor were developed. The optimum drop shaped pin array was shown to match the heat transfer rates obtained by the optimum circular pin configuration while incurring less than one third the specific fluid friction power losses. The data and conclusions of this study can be applied to the optimization of different heat exchangers which are used in industry, especially oil cooler in power transformers which are currently working with low cooling efficiency. It can also be used in the design of electronic components, turbine blade cooling or in other high heat flux dissipation applications requiring a low-profile, high area-density based micro-heat exchanger design. This study also shows that numerical models backed with experimental analysis can reduce both the time and money required to create and evaluate engineering concepts, especially those that deal with fluid flow and heat transfer. In the following chapters, first the problems which are encountered by power transformer suppliers are described. Then pin fin technology is studied with more details as a novel solution to the oil cooling problem. Some studies on behavior of power transformer coolers are also conducted to make their problems more clear. Available experimental data in the Iran Transfo company have been used for validation of these studies. They are presented as separated papers at the end of thesis. Finally the results of pin fin studies are presented and horizontal continuous casting (HCC) is explained as a manufacturing method for pin fins production. A separate paper which is based on experimental study on HCC is also included at the end of thesis.
Forskningen presenterad är ett resultat av en numerisk studie av värmeöverföring och tryckfall i en värmeväxlare designad med olika former av Kylflänsar. Värmeväxlaren består av ett rektangulärt kanal utrustat med olika former av Kylflänsar och är uppvärmd underifrån. Kylflänsar forma och den kompakta värmeväxlarens utformning är studerade numeriskt för att maximera värmeöverföringen och minimera tryckfallet över värmeväxlaren.En tredimensionell finit volym baserad på en numerisk modell i FLUENT© användes för att analysera värmeöverföringsegenskaper för olika Kylflänsar konfigurationer. Genom simuleringar uppskattades värmegenomgångstalet och tryckfallet för olika Reynolds tal och Kylflänsar konfigureringar. Cirkulära Kylflänsar konfigurationer inkluderar variation av avstånd mellan Kylflänsar, och förhållandet mellan axiellt avstånd och höjd. Rektangulära och droppformade Kylflänsar inkluderade även variation för längd och aspekt förhållande. Korrelation mellan Nusselts tal och friktionsfaktor utvecklades. Optimal matris för hur droppformade Kylflänsar placerades visades överensstämma med optimal överföring för cirkulära Kylflänsar men bara med en tredjedel av friktionsförlusterna för fluiden. Data och slutsatser från studien kan användas inom för optimering av värmeväxlare använda i industrin, speciellt oljekylda högspänningstransformatorer som har låg effektivitet i kylningen. Resultaten kan även användas inom design av elektronikkomponenter, kylning av turbinblad eller andra komponenter med högt värmeflöde där låg profil, och stor ytdensitet behövs. Studien visar att kombinationen av numeriska modeller som valideras genom experiment kan reducera både tid och kostnad vid utveckling och utvärdering av ingenjörsverktyg, speciellt inom fluidmekanik och värmeöverföring. I följande kapitel beskrivs först problem som identifierats av tillverkare av högspänningstransformatorer. Kylflänsar studeras i detalj som en ny lösning till de identifierade problemen med oljekylning. Några studier har genomförts för att ytterligare belysa problemen kring högspänningstransformatorers kylning. Tillgängliga data från Iran Transfo company har använts för validering av resultat från studierna. Studierna presenteras som separata artiklar i slutet av avhandlingen. Avslutningsvis presenteras resultat från studierna av Kylflänsar och en horisontell kontinuerlig gjutprocess (HCC) för tillverkning av Kylflänsar. HCC-studien presenteras som en separat artikel inkluderad sist i avhandlingen.
Randell, Per. "Numerical Simulation of Temperature and Velocity Profiles in a Horizontal CVD-reactor." Thesis, Linköpings universitet, Mekanisk värmeteori och strömningslära, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-117942.
Yesilyurt, Gokhan. "Numerical simulation of flow distribution for pebble bed high temperature gas cooled reactors." Texas A&M University, 2004. http://hdl.handle.net/1969.1/372.
Gibson, Jeffrey Reed. "Direct Numerical Simulation of Transonic Wake Flow in the Presence of an Adverse Pressure Gradient and Streamline Curvature." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2795.
Kumar, Deepak. "Numerical simulation of flows in an active air intake device of internal combustion engine with pulsated air flow." Thesis, Ecole centrale de Nantes, 2018. http://www.theses.fr/2018ECDN0004/document.
The exhaust emissions from automobiles are one of the major sources of air pollution in today’s world. Thence,research and development is the key feature of the modern automotive industries to meet strict emission legislation. One of the key aspects to meet these requirements is to improve the gas exchange process within internal combustion engines. It is possible by the design optimization of the air intake manifolds for internal combustion engines. One of such advancement in air intake manifolds is variable tumble systems (VTS). In VTS system, tumble flaps are installed at the exit of the manifold runner in order to improve tumble ratio and hence air-fuel mixing. Another feature of the flow inside the intake manifolds is pressure pulsation effect. Therefore, the aim of the Ph.D. work is to simulate the pulsating air flow inside the air intake manifolds and to identify the effect of the pressure pulsations on the active components like tumble flaps. The simulation work in the present thesis has been carried out on open source CFD code OpenFOAM. In a first step, the effect of pressure pulsations is simulated inside a steel tube and a simulation methodology is developed. The results of the simulation are validated on a specific experimental device, the dynamic flow bench. Then,simulations have been carried out on the main intake manifold with tumble flaps. Firstly, the simulations are performed with five different opening positions of the tumble flap in a steady state configuration. The forces and moments acting on the flap in steady state are obtained and analyzed. Then, unsteady simulations with pressure pulsation effects are performed. The results of obtained from unsteady simulation are compared with the experimental results in terms of relative pressure fluctuations. The effect of the pressure pulsation on the aerodynamic forces and moments acting on the tumble flaps are analyzed and explained
Lemoine, Gaëtan. "Étude expérimentale et numérique d’écoulements réactifs en conditions hydrothermales : mélanges de fluides et précipitation de sels." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0235/document.
HydroThermal Oxidation (HTO) is one of the technologies applied for radio-contaminated organic liquid waste treatment. HTO uses the peculiar properties of supercritical water to achieve a complete destruction of organic compounds within very short residence times in continuous compact reactors. A thermohydraulic model, coupled with combustion kinetics, was previously developed by the CEA, and implemented using CFD software ANSYS Fluent. In order to improve the description of the flow in continuous HTO reactors, mixtures density measurements allowed to find a model fitting these experimental data. This model was consequently incorporated into the previous numerical simulation. The issue of mineral salts precipitation was also taken into account, by an experimental methodology allowing to acquire solubility data of model compounds, and also to collect and characterise the deposit obtained after precipitation of these compounds in an ad hoc continuous device. This experimental work was followed by the implementation of these precipitation and deposition phenomena in the numerical model
Rojatkar, Prachi. "Numerical Simulation of 3-D Turbulent Room Airflow Pattern and Temperature Field in UC Solar Decathlon House." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1196019483.
Mompó, Laborda Juan Manuel. "Engineering Large Eddy Simulation of Diesel Sprays." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/37345.
Mompó Laborda, JM. (2014). Engineering Large Eddy Simulation of Diesel Sprays [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/37345
TESIS
Park, Jeanhyuk. "NUMERICAL STUDY OF CONCURRENT FLAME SPREAD OVER AN ARRAY OF THIN DISCRETE SOLID FUELS." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case151492595770856.
Khallahle, Jack Buckhill. "Numerical Simulation of Flow Parameters in Stratified Gas-Liquid Flow in a Horizontal Pipe." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29931.
Claramunt, Altimira Kilian. "Numerical Simulation of Non-premixed Laminar and Turbulent Flames by means of Flamelet Modelling Approaches." Doctoral thesis, Universitat Politècnica de Catalunya, 2005. http://hdl.handle.net/10803/6680.
One of the limitations to design combustion equipments, or even predict simple flames, is the resolution of the mathematical formulation. Analytical solutions are not feasible, and recently numerical techniques have received enormous interest. Even though the ever-increasing computational capacity, the numerical resolution requires large computational resources due to the inherent complexity of the phenomenon (viz. multidimensional flames, finite rate kinetics, radiation in participating media, turbulence, etc). Thus, development of capable mathematical models reducing the complexity and the stiffness as well as efficient numerical techniques are of great interest.
The main contribution of the thesis is the analysis and application of the laminar flamelet concept to the numerical simulation of both laminar and turbulent non-premixed flames. Assuming a one-dimensional behavior of combustion phenomena in the normal direction to the flame front, and considering an appropriate coordinates transformation, flamelet approaches reduce the complexity of the problem.
The numerical methodology employed is based on the finite volume technique and a parallel multiblock algorithm is used obtaining an excellent parallel efficiency. A post-processing verification tool is applied to assess the quality of the numerical solutions.
Before dealing with flamelet approaches, a co-flow partially premixed methane/air laminar flame is studied for different levels of partial premixing. A comprehensive study is performed considering different mathematical formulations based on the full resolution of the governing equations and their validation against experimental data from the literature. Special attention is paid to the prediction of pollutant formation.
After the full resolution of the governing equations, the mathematical formulation of the flamelet equations and a deep study of the hypothesis assumed are presented. The non-premixed methane/air laminar flame is considered to apply the flamelet modelling approach, comparing the results with the simulations obtained with the full resolution of the governing equations. Steady flamelets show a proper performance to predict the main flame features when differential diffusion and radiation are neglected, while unsteady flamelets are more suitable to account for these effects as well as pollutant formation. Assumptions of the flamelet equations, the scalar dissipation rate modelling, and the evaluation of the Lagrangian flamelet time for unsteady flamelets are specially analysed.
For the numerical simulation of turbulent flames, the mathematical formulation based on mass-weighted time-averaging techniques, using RANS EVM two-equation models is considered. The laminar flamelet concept with a presumed PDF is taken into account. An extended Eddy Dissipation Concept model is also applied for comparison purposes. A piloted non-premixed methane/air turbulent flame is studied comparing the numerical results with experimental data from the literature. A clear improvement in the prediction of slow processes is shown when the transient term in the flamelet equations is retained. Radiation is a key aspect to properly define the thermal field and, consequently, species such as nitrogen oxides. Finally, the consideration of the round-jet anomaly is of significant importance to estimate the flame front position.
In conclusion, flamelet modelling simulations are revealed to be an accurate approach for the numerical simulation of laminar and turbulent non-premixed flames. Detailed chemistry can be taken into account and the stiffness of the chemistry term is solved in a pre-processing task. Pollutant formation can be predicted considering unsteady flamelets.
Garg, Dhiraj Kumar. "Numerical modeling and simulation of polymerization reactions in coiled flow inverters." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAE002/document.
This thesis aimed at improving the modeling and simulation of free radical polymerization (FRP) in batch as well as in flow reactors. A generalized explicit analytical solution (AS) was obtained in case of variable volume, bulk/solution polymerization, homogeneous and isothermal batch reactor. The reaction steps included initiation, propagation, transfer to monomer, transfer to solvent, transfer to chain transfer agent (CTA), termination by combination and disproportionation. Different models of gel, glass and cage effects were also implemented explicitly. AS was validated against numerical solutions as well as published experimental data and was found in good agreement. Furthermore, its applicability was extended to conditions for which AS was not derived, i.e. non-isothermal conditions. The versatility and flexibility of AS over the complete range of monomer conversion were thus demonstrated. Then, to broaden its applications range even more, AS was used in CFD simulations. A new and simple transformation was proposed to make kinetic rate coefficients dimensionless in terms of concentration. This enabled chemical data to be fed in molar form to CFD modeling. It also enabled easy coding and debugging by keeping the original form of generation terms intact. The results were found to be improved after validation against experimental data. This transformation was then used for evaluating three tubula microreactor geometries, namely straight tube reactor (STR), coiled tube reactor (CTR) and coil flow inverter reactor (CFIR), under different feed conditions (unmixed or perfectly mixed) at very low Reynolds numbers (<1). The modeling for FRP was performed with constant or variable fluid physical parameters (density, viscosity and thermal conductivity) along with discrete variation of diffusion coefficients. Their effects on simulation results were observed and compared with published experimental data for 4 different monomers and were found to match perfectly. Results for mixed feed condition were found to be independent of microreactor geometry. CFIR seems to be the most promising reactor design under microreaction investigated conditions as it allowed the best control over polymer characteristics
Afailal, Al Hassan. "Numerical simulation of non-reactive aerodynamics in Internal Combustion Engines using a hybrid RANS/LES approach." Thesis, Pau, 2020. http://www.theses.fr/2020PAUU3028.
Internal aerodynamics is a key element for improving the combustion efficiency in Spark-Ignition (SI) engines. Within this context, CFD tools are increasingly used to investigate in-cylinder flows and to support the design of fuel-efficient engines. The present research aimed at extending and validating a non-zonal hybrid Reynolds-Averaged Navier-Stokes / Temporal Large-Eddy Simulation (HTLES) approach, initially formulated for stationary flows, to cyclic SI engine flows with moving walls. The aim was to model the near-wall regions and coarse mesh regions in RANS, while solving the turbulent scales in core regions with sufficient mesh resolution using temporal LES, in a seamless approach with no a priori user input. HTLES was retained as it proposed a consistent hybridization combining time-averaging in RANS regions with temporal filtering in TLES.A first development consisted in implementing a smooth shielding function that enforces the RANS mode in near-wall regions, regardless of the local temporal and spatial resolution. The extension of HTLES to cyclic flows was then achieved via the formulation of a method allowing approximating the phase averages of resolved flow quantities based on an Exponentially Weighted Average (EWA). A dynamic expression for the width of the weighted average was proposed, in order to ensure that the high frequency turbulent fluctuations be filtered out from the resolved quantities, while keeping the low frequency cyclic components of the flow variables. The resulting EWA-HTLES model was implemented in the commercial CONVERGE CFD code. The developed EWA-HTLES model was first applied to the simulation of two steady flow configurations: a minimal turbulent channel and a steady flow rig. Predictions were confronted with reference data, as well as with those from RANS and LES. All simulations relied on the use of standard wall laws and coarse grids at walls. Imposing the RANS mode at walls yielded EWA-HTLES predictions of pressure losses much closer to DNS and experimental findings than with LES. At the same time, it allowed yielding results in terms of mean and RMS velocities s in the core regions of the same quality than LES, and superior to RANS.Finally, EWA-HTLES was applied to the simulation of two cyclic flows representative of SI engines: the compressed tumble and the Darmstadt single-cylinder pentroof 4valve engine. For each configuration, a total number of 40 consecutive cycles were simulated. The results were confronted to PIV data, and to RANS and LES predictions obtained using the same numerical set-up. It was shown that EWA-HTLES successfully drives the RANS-to-LES transition in such complex configurations exhibiting unsteady flow features and important cyclic geometrical deformations. It switched from the RANS mode at the walls to LES in the core region of the cylinder, allowing a better prediction of unsteady phenomena including the evolution of the overall tumble characteristics and phenomena associated to cyclic variability. The EWA-HTLES results were shown to be comparable to those predicted by LES, and superior to RANS.The performed developments and obtained results open encouraging perspectives for the application of this hybrid RANS/LES method in industrial configurations involving non-stationary conditions and in particular moving boundaries
Volk, Annette. "Quantification of Numerical and Modeling Errors in Simulation of Fluid Flow through a Fixed Particle Bed." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1448275079.
Navarro, García Roberto. "A numerical approach for predicting flow-induced acoustics at near-stall conditions in an automotive turbocharger compressor." Doctoral thesis, Universitat Politècnica de València, 2014. http://hdl.handle.net/10251/44114.
Navarro García, R. (2014). A numerical approach for predicting flow-induced acoustics at near-stall conditions in an automotive turbocharger compressor [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/44114
TESIS
Premiado
De, Oliveira Campos Leandro Dijon. "Mass transfer coefficients across dynamic liquid steel/slag interface." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0554/document.
In order to characterize the mass transfer coefficients (MTC) of different species across liquid steel/slag interface, a multiphase Computational Fluid Dynamic (CFD) model was developed. MTC’s are estimated from models based on physicochemical and hydrodynamic parameters, such as mass diffusivity, interface shear and divergence strength. These models were developed for gas-liquid interactions with relative low Schmidt (Sc=ν⁄D) numbers (Sc≈200). However, the industrial processes involve mass transfer of chemical species with Sc number ranging from 103 to 104. To evaluate the applicability of these existing models, the fluid flow in the vicinity of a liquid/liquid interface is investigated. Computational Fluid Dynamic (CFD) and Laser Doppler Anemometry (LDA) were used to calculate and measure the velocity field on a continuous casting (CC) water model configuration. The work provides new insights and original measures to understand the fluid flow near liquid-liquid interfaces.The mass transfer model of an industrial continuous casting mold showed that the mass transfer coefficients are not homogeneously distributed, and slag properties should follow this trend. This non-homogeneity was confirmed by physical experiments performed with a water model of a CC configuration and its CFD representation. The calculated flow was used to predict the MTC and the interface area between phases, since the interface is constantly moving. These parameters will be the input of thermodynamic models to predict slag composition and viscosity. This methodology is currently under validation, and it will also be applied to improve steel plant performance in the desulphurization process
Chen, Qing [Verfasser]. "Numerical investigation of internal flow in hydraulic valves and dynamic interactions in hydraulic systems with CFD and simplified simulation methods / Qing Chen." Aachen : Shaker, 2005. http://d-nb.info/1181607736/34.
Almeida, Fernando Mattavo de. "Numerical simulation of the flow through an aqxial tidal-current turbine employing an elastic-free-surface approach." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3135/tde-18092018-074509/.
O crescimento econômico mundial e o aumento na demanda pela geração de energia andam juntos. No entanto, uma maior capacidade de produção de energia poderia afetar negativamente o meio ambiente. Mesmo as fontes limpas e renováveis, como a hidrelétrica e a eólica acarretam em impactos socioeconômicos e ambientais. Por exemplo, a construção de uma usina hidrelétrica demanda uma imensa área alagada que pode devastar florestas inteiras e a instalação de uma usina eólica pode afetar a migração de certas espécies de pássaros e produzir altos níveis de barulho. Portanto, para equilibrar as vantagens e desvantagens devidas a cada meio de produção de energia, é necessária a diversificação, que demanda de investimentos em novas fontes. Neste contexto, a geração de energia nos oceanos é destacada. O primeiro ponto a respeito desta fonte é de que não há a necessidade de remoção da população na área de instalação, tal como os métodos de geração dentro do continente. O segundo principal ponto é a respeito da distribuição de energia. A maior parte da população mundial vive em regiões costeiras, diminuindo, portanto, a distância entre a produção e demanda, reduzindo assim, seus custos. As duas principais metodologias para se explorar a energia proveniente dos oceanos são: Energia de Ondas e Energia de Marés. E considerando que os ciclos de mare são governados principalmente pela interação gravitacional entre os oceanos, lua e sol, eles são facilmente previsíveis, o que aumenta a confiabilidade dos sistemas de geração de energia baseados em marés. Este trabalho explora as metodologias para analisar a geração de energia a partir de uma única turbina axial de corrente de maré através de uma metodologia baseada nas equações de Navier-Stokes com a média de Reynolds, analisadas em regime permanente. São discutidos efeitos da direção do escoamento, perfil de velocidades na entrada e nos níveis de turbulência. Os resultados são comparados com experimentos. É proposta uma metodologia alternativa para a modelagem da superfície livre com CFD uma vez que a metodologia atual é baseada em um escoamento bifásico que demanda de um refinamento adicional da malha e é computacionalmente caro. A nova metodologia usa uma parede elástica na região da superfície livre com a rigidez ajustada para se obter o mesmo efeito de restauração que a gravidade. De maneira geral, os resultados para o domínio aberto se aproximaram dos resultados experimentais, validando o modelo numérico e além disso, o modelo considerando confinamento da turbine mostrou maiores valores para os coeficientes de potência e empuxo, estando portanto, de acordo com a teoria do disco atuador. O modelo com a superfície livre elástica apresentou problemas de convergência, relacionados com números de Froude elevados, uma vez que isto se relaciona com maiores deformações na região da superfície livre. Uma simulação com 10% da velocidade original foi realizada, obtendo-se resultados coerentes para ambos coeficientes de potência e empuxo.
Vieira, Edson Rodrigo Del Rio Vieira [UNESP]. "Análise in silico do escoamento hemodinâmico em aneurismas cerebrais do tipo basilar." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/145008.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Segundo a Sociedade de Cirurgia Vascular da América do Norte e Sociedade Internacional de Cirurgia Cardiovascular, aneurismas são dilatações superiores ou iguais a 1,5 vezes o diâmetro original da artéria. Estima-se que aproximadamente 2% a 5% da população adulta tem algum tipo de aneurisma cerebral. Grande parte dos casos não chegam a causar sintomas ou gerar problemas graves, entretanto o risco de sua ruptura gera consequências clínicas desafiadoras, visto que tem grande taxa de morbimortalidade, tornando difícil a tarefa de tomar a decisão de intervenção ou não no tratamento do aneurisma. Neste trabalho, propõe-se o estudo numérico do escoamento em aneurismas do tipo basilar empregando-se a técnica da dinâmica de fluidos computacional. Comparando diferentes casos de aneurismas rompidos e não rompidos, identificamos características no escoamento para auxiliar a tomada de decisões no tratamento de pacientes. Os casos de aneurismas são oriundos de tomografias computadorizadas de pacientes reais, os quais foram utilizados para a criação dos modelos digitais. As simulações computacionais foram realizadas com oprogramaopen sourceOpenFOAM® . Outros programasopen source também foram utilizados na criação dos modelos, assim como para o tratamento dos resultados. Identificamos uma correlação entre os dados de tensão cisalhante na parede e a probabilidade de ruptura. Para os oito casos estudados, os resultados de previsão de ruptura e não ruptura apresentaram grande compatibilidade. Dentre os quatrocasos de aneurismas previamente reconhecidos como rompidos, trêsforam identificados pelas simulações comoaneurismas com alto risco de ruptura e umfoi identificado com risco intermediário de ruptura. Já para os quatro casos de aneurismas previamente reconhecidos como rompidos, doisforam identificados pelas simulações como aneurismas de baixo risco de ruptura e doiscom risco intermediário de ruptura.
According to the Society for Vascular Surgery of North America and the International Society of Cardiovascular Surgery, aneurysms are dilations greater than or equal to 1.5 times the original artery diameter.It is estimated that approximately 2% to 5% of adult population has some type of brain aneurysm. In most cases aneurysms are small enough not to cause symptoms or serious problems, however the risk of rupture generates challenging clinical consequences, since they have high rate of morbidity and mortality, making difficult the decision whether or not to treat the aneurysm. This work presents the study of the flow through the basilar type aneurysms using the technique of computational fluid dynamics. Comparing different cases of ruptured and nonruptured aneurysms, we identified some flow characteristics that can help in the decision making process for the treatment of patients. The cases studied were taken from CT scans of real patients, which were used for creation of digital models of aneurysm used in the simulations. The simulations were performed using open source software OpenFOAM® . Others open source softwares were also used in the creation of models as well as for post processing. We investigated the correlation between wall shear stress and the likelihood of rupture. For the eight cases, the rupture prediction results showed good correlation. For the four ruptured cases simulated, three were identified with high risk of rupture and one with intermediary risk of rupture. As for the four not ruptured cases, two were identified with low risk of rupture and two with intermediary risk of rupture.
CNPq: 134375/2015-7
Li, Shuo. "A Numerical Study of Micro Synthetic Jet and Its Applications in Thermal Management." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7539.
Fimbres, Weihs Gustavo Adolfo UNESCO Centre for Membrane Science & Technology Faculty of Engineering UNSW. "Numerical simulation studies of mass transfer under steady and unsteady fluid flow in two- and three-dimensional spacer-filled channels." Publisher:University of New South Wales. UNESCO Centre for Membrane Science & Technology, 2008. http://handle.unsw.edu.au/1959.4/41453.