One-Equation RG Hybrid RANS/LES Modelling
A one-equation variant of a previously developed two-equation, renormalization group (RG) based, hybrid RANS/LES model is presented. The model has a transport equation for the mean dissipation rate and an algebraically prescribed length scale. The length scale is proportional to the wall distance in RANS regions of the flow and to the filter width in LES regions. A near-wall formulation is used in the manner of Yakhot and Orszag’s RNG modelling. The only free parameter entering the low-Reynolds formulation has been calibrated against channel flow, and the value corresponds well with experimental values for the same parameter obtained for decaying homogeneous isotropic turbulence. Applications to an impinging jet and a plane asymmetric diffuser are presented.
KeywordsRenormalization Group Turbulent Kinetic Energy Filter Width Shear Stress Profile Dynamic Smagorinsky Model
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- De Langhe, C., Merci, B., Dick, E.: Hybrid RANS/LES modelling with an approximate renormalization group. I. Model development. Journal of Turbulence 6(13) (2005a)Google Scholar
- De Langhe, C., et al.: Hybrid RANS/LES modelling with an approximate renormalization group. II. Applications. Journal of Turbulence 6(14) (2005b)Google Scholar
- Hadziabdić, M.: LES, RANS and Combined Simulation of Impinging Flows and Heat Transfer. PhD Thesis Technical University Delft (2006)Google Scholar
- Obi, S., Aoki, K., Masuda, S.: Experimental and computational study of turbulent separating flow in an asymmetric plane diffuser. In: Proceedings 9th Symposium on Turbulent Shear Flows, Kyoto, Japan, pp. 305–1–305–4 (1993)Google Scholar