LES of H2-air jet combustion in high enthalpy supersonic crossflow

Abstract

Here, we report on large eddy simulation (LES) of supersonic flow, mixing, self-ignition, and combustion in a supersonic hydrogen jet in a crossflow configuration. The configuration has been experimentally investigated at Stanford and consists of a rectilinear channel with a ramp inlet in which a hydrogen jet discharges at a 90° angle to the high enthalpy supersonic crossflow. This configuration has been extensively studied by several research groups and constitutes a good validation case for model development and physics elucidation. The LES model used is based on an unstructured finite volume discretization of the filtered mass, momentum, species, and energy equations and an explicit flow solver. In this study, we investigate the effects of the jet-to-crossflow momentum ratio, the chemical reaction mechanism, and the combustion subgrid model by comparing predictions and by comparing with experimental data including OH* chemiluminescence images and jet penetration data. In general, good agreement is found but with some departures for the smallest reaction mechanisms and some of the LES combustion models. The LES results are also used to elucidate the flow, mixing, and combustion features of this configuration.