Knudsen number dependence of 2D single-mode Rayleigh-Taylor fluid instabilities

Autor:	Sagert, Irina, Howell, Jim, Staber, Alec, Strother, Terrance, Colbry, Dirk, Bauer, Wolfgang
Rok vydání:	2014
Předmět:	Physics - Fluid Dynamics Astrophysics - Instrumentation and Methods for Astrophysics
Druh dokumentu:	Working Paper
DOI:	10.1103/PhysRevE.92.013009
Popis:	We present a study of single-mode Rayleigh-Taylor instabilities (smRTI) with a modified Direct Simulation Monte Carlo (mDSMC) code in two dimensions. The mDSMC code is aimed to capture the dynamics of matter for a large range of Knudsen numbers within one approach. Our method combines the traditional Monte Carlo technique to efficiently propagate particles and the Point-of-Closest-Approach method for high spatial resolution. Simulations are performed using different particle mean-free-paths and we compare the results to linear theory predictions for the growth rate including diffusion and viscosity. We find good agreement between theoretical predictions and simulations and, at late times, observe the development of secondary instabilities, similar to hydrodynamic simulations and experiments. Large mean-free-paths favor particle diffusion, reduce the occurrence of secondary instabilities and approach the non-interacting gas limit. Comment: 15 pages, 12 figures, 1 table
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1410.6420 Zobrazit plný text záznamu View this record from Arxiv