Turbulence model large eddy simulation

Dirbulence causes swirls or eddies in turbulent flow with different length and time scales. It is almost impossible to accurately computationally describe turbulent flow with all eddies included because this would require very powerful computers. Scientists and engineers have therefore developed different turbulence models, such as k-e model, k-a model, large eddy simulation (LES) model, or direct numerical simulation (DNS) model, which are accurate enough to mimic real-world turbulent flow. 

Another detailed method of determining pressures is computational fluid dynamics (CFD), which uses a numerical solution of simplified equations of motion over a dense grid of points around the building. Murakami et al. and Zhoy and Stathopoulos found less agreement with computational fluid dynamics methods using the k-e turbulence model typically used in current commercial codes. More advanced turbulence models such as large eddy simulation were more successful but much more costly. ... 

David.son, L, Large eddy simulation A dynamic one-equation subgrid model for three-dimensional recirculating flow. In llth Int. Symp. on Turbulent Shear Flow, vol. 3, pp. 26.1-26.6, Grenoble, 1997. 

The ability to resolve the dissipation structures allows a more detailed understanding of the interactions between turbulent flows and flame chemistry. This information on spectra, length scales, and the structure of small-scale turbulence in flames is also relevant to computational combustion models. For example, information on the locally measured values of the Batchelor scale and the dissipation-layer thickness can be used to design grids for large-eddy simulation (LES) or evaluate the relative resolution of LES resulfs. There is also the potential to use high-resolution dissipation measurements to evaluate subgrid-scale models for LES. 

Colin, O., et al., A thickened flame model for large-eddy simulations of turbulent premixed combustion. Phi/s. Fluids, 2000.12(7) 1843-1863. 

Van Vliet, E., Derksen, J. J., and Van den Akker, H. E. A., Modelling of Parallel Competitive Reactions in Isotropic Homogeneous Turbulence Using a Filtered Density Function Approach for Large Eddy Simulations . Proc. PVP01 3rd Int. Symp. on Comput. Techn. for Fluid/Thermal/Chemical Systems with Industrial Appl., Atlanta, GE, USA (2001). 

Vedula, P., P. K. Yeung, and R. O. Fox (2001). Dynamics of scalar dissipation in isotropic turbulence A numerical and modeling study. Journal of Fluid Mechanics 433, 29-60. Verman, B., B. Geurts, and H. Kuertan (1994). Realizability conditions for the turbulent stress tensor in large-eddy simulations. Journal of Fluid Mechanics 278, 351-362. Vervisch, L. (1991). Prise en compte d effets de cinetique chimique dans lesflammes de diffusion turbulente par Tapproche fonction densite de probabilite. Ph. D. thesis, Universite de Rouen, France. 

Wall, C., B. J. Boersma, and R Moin (2000). An evaluation of the assumed beta probability density function subgrid-scale model for large eddy simulation of nonpremixed, turbulent combustion with heat release. Physics of Fluids 12, 2522-2529. 

DesJardin, P. E., and S. H. Frankel. 1998. Large-eddy simulation of a turbulent nonpremixed reacting jet Application and assessment of subgrid-scale combustion models. J. Physics Fluids 10(9) 2298-314. 

Jaberi, F. A., and S. A. James. 1998. A dynamic similarity model for large eddy simulation of turbulent combustion. J. Physics Fluids 10(7) 1775-77. 

Zhang, W., Hamer, A., Klassen, M., Carpenter, D., and Roby, R. Turbulence statistics in a fire room model by large eddy simulation. Fire Safety Journal, 2002. 37(8), 721-752. 

Meneveau, C., and J. Katz. 2000. Scale-invariance and turbulence models for large-eddy simulations. Annual Reviews Fluid Mechanics. 1-32. 

The three main numerical approaches used in turbulence combustion modeling are Reynolds averaged Navier Stokes (RANS) where all turbulent scales are modeled, direct numerical simulations (DNS) where all scales are resolved and large eddy simulations (LES) where larger scales are explicitly computed whereas the effects of smaller ones are modeled ... 

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