Subgrid models in turbulent mixing
نویسندگان
چکیده
We are concerned with the chaotic flow fields of turbulent mixing. Chaotic flow is found in an extreme form in multiply shocked Richtmyer-Meshkov unstable flows. The goal of a converged simulation for this problem is to obtain converged solutions for such micro solution features as the joint probability distributions of the temperature and species concentration, as well as the macro features such as the edges of the mixing region. Here we introduce parameterized subgrid models of mass and thermal diffusion, to define LES that replicate the micro features observed in the DNS. The Schmidt numbers and Prandtl numbers are chosen to represent typical liquid and gas parameter values. The viscosity, and thus the Reynolds number, is allowed to vary through a range of values, to allow exploration of both DNS and LES regimes. Our main result is to explore the dependence of these solutions on mesh and Reynolds number.
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