Search for dissertations about: "Turbulence Modeling"

Showing result 6 - 10 of 125 swedish dissertations containing the words Turbulence Modeling.

2. 6. Computational Modeling of Complex Flows

   Author : Johan Hoffman; Göteborgs universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; computational fluid dynamics; adaptive finite element method; a posteriori error estimate; subgrid modeling; transition to turbulence; multiresolution analysis; object-oriented software; computational fluid dynamics;

   Abstract : In this thesis we consider the following aspects of computational modeling of complex flows: (i) subgrid modeling, (ii) stability, (iii) a posteriori error estimation, and (iv) computational platform. We develop a framework for adaptivity and error control for multiscale problems, in particular for turbulent flow, based on a posteriori error estimates. READ MORE

4. 7. Explicit algebraic subgrid-scale stress and passive scalar flux modeling in large eddy simulation

   Author : Amin Rasam; Arne V. Johansson; Shia-Hui Peng; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Turbulence; Large eddy simulation; explicit algebraic subgrid-scale model; passive scalar; stochastic modeling; backscatter; Fluid mechanics; Strömningsmekanik;

   Abstract : The present thesis deals with a number of challenges in the field of large eddy simulation (LES). These include the performance of subgrid-scale (SGS) models at fairly high Reynolds numbers and coarse resolutions, passive scalar and stochastic modeling in LES. READ MORE

5. 8. Turbulence-resolving Simulations of Swirling Flows

   Author : Ardalan Javadi; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Swirling Flow; URANS; Hydropower; Hybrid URANS-LES; SAS; Flow Control; Turbulence Modeling; Vortex Breakdown; DDES; LES;

   Abstract : A series of numerical investigations is undertaken using a wide range of turbulence mod-els including conventional and non-conventional URANS models, hybrid URANS-LESmethods and LES to capture a large variety of physical mechanisms that produce pres-sure pulsations in the swirling flows. The available knowledge about these pulsations,which are usual in hydropower, are still far from complete. READ MORE

6. 9. The One-Dimensional Turbulence Model Applied to Spray Atomization

   Author : Amirreza Movaghar; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Primary breakup; Turbulence; One Dimensional Turbulence ODT ;

   Abstract : Numerical simulation of the spray behavior is an important part of engine research and is critical for combustion optimization. Successful implementation of the advanced modeling tools for sprays is strongly dependent on our current understanding of the physical processes involved. READ MORE

7. 10. CFD Modeling of Turbulent Flows in Industrial Applications with Emphasis on Premixed Combustion in Gas Turbines

   Author : Ulf Engdar; Kraftverksteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; framdrivningssystem; Motorer; turbulence and premixed combustion modeling ; CFD modeling ; level-set flamelet library approach ; emissions ; gas turbine ; compressor washing ; spray modeling ; Technological sciences; Teknik; Energy research; Energiforskning; Thermal engineering; applied thermodynamics; Termisk teknik; Motors and propulsion systems; termodynamik;

   Abstract : Increasing restrictions on hazardous emissions combined with demands for good profitability from the operators in the energy market have contributed strongly to the development of innovations in which the emphasis is on low emissions and high efficiency. For gas turbine-based power plants, emission of NOx in particular is governed by stringent legislation. READ MORE