Доступ предоставлен для: Guest
TSFP DL Home Архив Исполнительный Комитет

A NON-EQUILIBRIUM MODEL FOR SCALAR DISSIPATION RATE IN LES OF COMBUSTION

Colleen M. Kaul
Department of Aerospace Engineering and Engineering Mechanics, The University of Texas at Austin Austin TX, USA, 78712

Venkatramanan Raman
University of Texas at Austin, W. R. Woolrich Laboratories, 210 East 24th Street, Austin, Texas 78712-0235, USA

Аннотация

Modeling of subfilter scalar dissipation rate is critical to accurate simulation of turbulent combustion using large eddy simulation (LES). Non-equilibrium models contain a timescale coefficient bτ that is generally unknown a priori and cannot be determined by conventional dynamic modeling procedures. Here, an alternative dynamic procedure is formulated from the variance transport equation (VTE). The modeling accuracy of the VTE-based dynamic model for bτ is assessed through a priori tests in homogeneous isotropic turbulence and in a planar jet flow. Particular attention is given to the effects of various averaging methods used for coefficient estimation and a novel conditional averaging approach is presented.