Numerical Comparisons Between URANS and Hybrid RANS/LES at a High Reynolds Number Flow Using Unstructured Meshes
Ju-Yeol You/Oh Joon Kwon
International Journal of Aeronautical and Space Sicences, vol. 11, no. 1, pp.41-48, 2010
Abstract : In the present study, the turbulent flow fields around a circular cylinder at Re=3.6¥ª106 were investigated based on an unstructured mesh technique, and the comparisons between URANS(S-A, SST) and hybrid RANS/LES(DES, SAS) methods for the simulation of high Reynolds number flow have been conducted. For this purpose, unsteady characteristics of vortex shedding and time-averaged quantities were compared. A quasi-steady solution-adaptive mesh refinement was also made for the URANS and hybrid RANS/LES approaches. The results showed that the simple changes in the turbulent length scale or source term of turbulent models made the flow fields less dissipative and more realistic in hybrid RANS/LES methods than the URANS approaches.
Keyword : Hybrid RANS/LES, URANS, Solution-adaptive mesh refinement, Unstructured meshes |