Assessment of conditional moment closure for ignition in compositionally and thermally stratified mixtures

Abstract

A conditional moment closure (CMC) model is developed to simulate auto-ignition in compositionally and thermally stratified mixtures. The performance of the CMC model is examined in a priori and a posteriori manners. Two-dimensional direct numerical simulations (DNSs) are performed to generate the data required for a priori and a posteriori tests. The DNS cases simulate the conditions similar to a stratified charge compression ignition (SCCI) combustion mode with compositionally and thermally stratified n-heptane/air mixtures in a constant volume. The cases feature two different levels of stratification with three mean temperatures. The CMC model is implemented into an open source computatio..