Subgrid-scale models for large-eddy simulations of compressible wall bounded flows

A comparative assessment of six subgrid-scale models is presented in the ca se of a compressible plane channel flow over isothermal walls, four of whic h are based on the recent mixed-scale model. A supersonic and a subsonic ca se In temporal development at Mach 1.5 and 0.5, respectively, are considere d for a Reynolds number equal to 3000, with comparison to the direct numeri cal simulations (DNS) of Coleman ct al. ( Coleman, G, N., Rim, J, and Moser , R. D., "A Numerical Study of Turbulent Supersonic Isothermal-Wall Channel Flow" Journal of Fluid Mechanics, Vol. 305, 1995, pp. 159-183) in the firs t case, and the incompressible DNS of Rim et al. (Kim, J., Moin, P., and Mo ser, R., "Turbulence Statistics in Fully Developed Channel Flow at Low Reyn olds Number" Journal of Fluid Mechanics, Vol. 177, 1987, pp. 133-166) in th e second case. For each Mach number, two grids are considered, with about 2 0 and 5 times less grid points as in the reference DNS, and the results are globally satisfactory, although not excellent. In particular, the wall fri ction is globally underestimated by about 10%, both in the subsonic and the supersonic cases. Among the models tested are several original combination s, which vanish at the wall without requiring any damping function. They ar e found to improve significantly upon the statistics, in particular near th e wall.