Numerical Simulation of a Buoyant Thermal Using the k-ϵ Turbulence Model

Abstract

Possibilities for describing turbulent mixing processes through the use of the two-equation k-? model modified to take into account the effects of streamline curvature and buoyancy are discussed. It is shown that one of the k-? model constants must have different values under stable and unstable conditions so that a correct description of the turbulence in stratified flows could be achieved. The results of numerical simulation of a buoyant thermal rising in a stratified environment are presented. The simulation is based on gas dynamics averaged equations for compressible flows. Calculations show that the turbulence parameters distribution is highly inhomogeneous, and the results depend largely upon the streamline curvature and buoyancy effects.