Study of combustion flow field in a scramjet engine under inflow oscillation variations based on OpenFOAM

Abstract

In this study, a compressible supersonic numerical model was established based on the open-source computational fluid dynamics software OpenFOAM. The supersonic air inflow was set in sinusoidal variation and gas hydrogen was employed as fuel for the DLR engine numerical simulation. The SST k-ω model and a 9-species 27-reaction hydrogen/oxygen chemical reaction model was employed as the turbulence and reaction mechanical kinetics models respectively. The effect of continuous variable inflow on the combustion performance for the scramjet engine was analyzed and the results showed that the combustion flame inside the scramjet engine exhibited significant partitioning phenomena around the combustion stabilization zones under periodic continuous variable inflow conditions. It was found that intense combustion zones were formed at both upstream and downstream flow as the induction of intersecting shock waves. When the flame was stabilized in the engine, the initiation position of the intense combustion zone at the upstream was transferred to the distance of twice the strut length, while the initiation position of the intense combustion zone at the downstream was anchored at a distance of about five times the strut length.