Numerical investigation of ${\rm H}_2$ injection in Mach 5 air flow with a strong shock/boundary layer interaction

Abstract.

A numerical study of the hydrogen injection has been investigated in a flow configuration obtained from the interaction of two axisymmetric oblique shock waves produced by a conical ring and a centre-body. This configuration, due to a strong shock/boundary layer interaction, was named a viscous mach interaction (VMI). The geometry which leads to this configuration can be used as a hypersonic inlet, and as this inlet could be axisymmetric or two-dimensional, a first result was to show that this VMI configuration exists in both cases. Different injection locations in the subsonic zone are tested in order to keep this VMI configuration . The influence of the hydrogen injection on the mixing flow behavior is analyzed. The numerical results show that the equivalence ratio $\Phi$ of the gas-mixture is high enough in order to have a non-reactive gas close to the wall which keeps constant the hydrogen temperature along the centre-body. Thus, the hydrogen injection can play the role of a forward-facing jet reducing heat-transfer at the centre-body wall.