Journal ArticleDOI
On nonlinear K-l and K-ε models of turbulence
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TLDR
In this paper, a nonlinear K-l and K-e model is proposed to predict the normal Reynolds stresses in turbulent channel flow much more accurately than the linear model, and the nonlinear model is shown to be capable of predicting turbulent secondary flows in non-circular ducts.Abstract:
The commonly used linear K-l and K-e models of turbulence are shown to be incapable of accurately predicting turbulent flows where the normal Reynolds stresses play an important role. By means of an asymptotic expansion, nonlinear K-l and K-e models are obtained which, unlike all such previous nonlinear models, satisfy both realizability and the necessary invariance requirements. Calculations are presented which demonstrate that this nonlinear model is able to predict the normal Reynolds stresses in turbulent channel flow much more accurately than the linear model. Furthermore, the nonlinear model is shown to be capable of predicting turbulent secondary flows in non-circular ducts - a phenomenon which the linear models are fundamentally unable to describe. An additional application of this model to the improved prediction of separated flows is discussed briefly along with other possible avenues of future research.read more
Citations
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Journal ArticleDOI
A Gas-Kinetic Scheme for Turbulent Flow
TL;DR: In this paper, the Boltzmann equation is used to model the dynamics of a turbulent tensor in the presence of large unresolved scales of motion, a sort of Knudsen number based on turbulent fluctuations, for which the Navier-Stokes model is not accountable.
Journal ArticleDOI
Numerical study of dispersing pollutant clouds in a built-up environment
TL;DR: In this paper, the dispersion of a passive scalar released from an instantaneous point source in a built-up (urban) environment using a Reynolds-averaged Navier-Stokes method was studied numerically.
Journal ArticleDOI
Assessment of the Performances of RANS Models for Simulating Swirling Flows in a Can-Combustor
K. Khademi Shamami,Madjid Birouk +1 more
TL;DR: In this article, the performance of RANS turbulence models for simulating turbulent swirling can-combustor flows with different inlet swirl intensities (i.e., S = 0.4 and S=0.81) was compared against published experimental data.
Dissertation
Vers la simulation des grandes échelles en formulation Euler-Euler des écoulements réactifs diphasiques
TL;DR: In this paper, a methode eulerienne instationnaire est proposee Des tests numeriques utilisant cette methode and la comparaisons avec des simulations identiques utilising un suivi lagrangien des particules montrent les possibilites and limites de la methode.
Journal ArticleDOI
Renormalization group analysis of anisotropic diffusion in turbulent shear flows
TL;DR: In this paper, the renormalization group is applied to compute anisotropic corrections to the scalar eddy diffusivity representation of turbulent diffusion of a passive scalar.
References
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Journal ArticleDOI
Progress in the development of a Reynolds-stress turbulence closure
TL;DR: In this article, the authors developed a model of turbulence in which the Reynolds stresses are determined from the solution of transport equations for these variables and for the turbulence energy dissipation rate E. Particular attention is given to the approximation of the pressure-strain correlations; the forms adopted appear to give reasonably satisfactory partitioning of the stresses both near walls and in free shear flows.
Journal ArticleDOI
A numerical study of three-dimensional turbulent channel flow at large Reynolds numbers
TL;DR: In this article, the three-dimensional, primitive equations of motion have been integrated numerically in time for the case of turbulent, plane Poiseuille flow at very large Reynolds numbers.
Journal ArticleDOI
Numerical investigation of turbulent channel flow
Parviz Moin,John Kim +1 more
TL;DR: In this article, a large-scale flow field was obtained by directly integrating the filtered, three-dimensional, time dependent, Navier-Stokes equations, and small-scale field motions were simulated through an eddy viscosity model.
Book ChapterDOI
Computational Modeling of Turbulent Flows
TL;DR: In this article, it is shown that direct simulation is not an alternative for practical computation and that the various sophisticated closures suffer from essentially the same problems as the direct simulations and therefore, are limited to homogeneous situations.
Journal ArticleDOI
A Reynolds stress model of turbulence and its application to thin shear flows
Kemal Hanjalic,Brian Launder +1 more
TL;DR: In this paper, the authors provided a model of turbulence which effects closure through approximated transport equations for the Reynolds stress tensor the turbulence energy κ and e.g., the turbulent shear stress does not vanish where the mean rate of strain goes to zero.