A comparison of mix models for the Rayleigh-Taylor instability

作者：Waltz J^*; Gianakon T A

来源：Computer Physics Communications, 2012, 183(1): 70-79.

DOI：10.1016/j.cpc.2011.08.018

• ICF simulation
• Turbulence modeling
• Rayleigh-Taylor

Four mix models, implemented into an Arbitrary Lagrangian-Eulerian (ALE) multi-physics code, are compared on simulations of the Rayleigh-Taylor instability. The specific models of interest are a mass diffusion model, the k-L turbulence model, the BHR turbulence model, and a multifluid interpenetration mix model. The bubble growth rates produced by the different models are compared to experimentally determined growth rates. The diffusion model reproduces the characteristic t(1/2) growth for diffusion processes and therefore does not reproduce instability growth rates, as expected. The k-L and BHR turbulence models reproduce the nominal instability growth rates at multiple Atwood numbers with a single set of model parameters. The multifluid interpenetration model exhibits diffusion-like behavior and therefore does not reproduce instability growth rates. All four models exhibit Cauchy-like convergence in the mixing layer width with decreasing mesh size, although the multifluid model exhibits both a larger error for a given mesh size and a slower convergence rate than the turbulence models.

• 出版日期2012-1