Turbulence modelling for rotating flows ( 2009)

Benoît de Laage de Meux __

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pdf	\\.host\Shared Folders\local01\demeux\WRITE\PRESENTATIONS\pres_umist_071009\slides_anglais_071009.pdf	manage	1704.0 K	2009-12-15 - 10:36	BenoitDeLaageDeMeux

Rotation and curvature greatly affect a turbulent motion. Basic effects of rotation on turbulence are non linear : two points correlations are modified in such a way that the Kolmogorov cascade is inhibited and the turbulence tends to become two dimensionnal. Moreover, competition beetween Coriolis force and viscous stress leads to instability phenomenon that can either increase or deacrease turbulence activity. This linear effect may be captured by a RANS closure.
A study concerning sensitization to rotation and curvature of turbulence RANS closure of Code_Saturne is reported in this presentation. It is shown that second ordrer closure can intrinsicly capture some Coriolis effects whereas Boussinesq eddy-viscosity closure can not. Three rotation/curvature (RC) corrections of eddy-viscosity models proposed in the litterature are introduced and test with three low Reynolds eddy-viscosity model : the Launder-Sharma, the k-omega SST and the phi-f. These RC-corrected eddy-viscosity models are compared with the near-wall second ordre closure EBRSM and DNS data in the spanwise rotating channel test case.