Large eddy simulation of Rayleigh–Taylor mixing based on helicity model

Abstract

This paper focuses on large eddy simulation of Rayleigh–Taylor instability (RTI) based on helicity model (HM) which is derived from our previous research. Based on the RTI problem, we obtain from a priori test and theoretical analysis that the suggested model can automatically distinguish laminar flow and turbulence. Comparing the numerical simulation results with direct numerical simulation (DNS) and traditional model in RTI problem, we could find that the suggested model overcomes some defects of the traditional model, such as the traditional model cannot predict transition accurately and the suggested model can predict the turbulence mixing width and mass fraction precisely. It provides a beneficial tool for the research of RTI.