An ILES analysis of transverse jet injection in to supersonic cross-flow with synthetic turbulent boundary layer

Sonic jet injection into a transverse supersonic turbulent flow (generally termed as JISC) is a very challenging field in aerodynamic modelling. The application of such a flow can be the active flow control in cavities during supersonic flights, thrust control system in rockets and the fuel injection in a scramjet combustion chamber. One important aspect of such a flow inside the scramjet combustion chamber is the turbulent boundary layer for the free-stream supersonic flow. In this work JISC is studied using a Godunov type implicit large eddy simulation (ILES) method, which employs fifth- and second-order accurate methods in space and in time, respectively, in conjunction with a digital filter based turbulent inflow data generation method. The free-stream flow is at Mach 1.6 and a sonic jet is injected in to this flow that penetrates and mixes with it to create complex flow features. Three grid levels are used to study grid convergence and the flow properties upstream and downstream of the jet injection for the instantaneous and averaged flow are analysed. It has been presented that Kelvin-Helmholtz (KH) instabilities in the upper jet shear layer are responsible for better mixing of the fluids. Moreover, it details the jet penetration, pressure distributions on the flat-plate, turbulent kinetic energy (TKE) and Reynolds stresses in the flow field downstream of the jet injection. The results are compared to the experimental data and recently performed classical LES for validation.