Conditional Moment Closure for Chemical Reactions in Laminar Chaotic Flows

摘要

We implement conditional moment closure (CMC)for simulation of chemical reactions in laminar chaotic flows.The CMC approach predicts the expected concentration of reactive species,conditional upon the concentration of a corresponding nonreactive scalar.Closure is obtained by neglecting the difference between the local concentration of the reactive scalar and its conditional average.We first use a Monte Carlo method to calculate the evolution of the moments of a conserved scalar;we then reconstruct the corresponding probability density function and dissipation rate.Finally,the concentrations of the reactive scalars are determined.The results are compared (and show excellent agreement)with full numerical simulations of the reaction processes in a chaotic laminar flow.