Numerical simulation on the unsteady supersonic combustion with transverse hydrogen

The processes of auto-ignition and combustion in a supersonic air flow with transverse hydrogen injection were calculated by solving the 2-D N-S equations through using an algebraic eddy-viscosity model, a two-step global chemical model and MacCormack explicit time-split method. The calculated results show that (1) the variation in static temperature, static pressure, velocity and fuel-air equivalent ratio in the process from the hydrogen injection, flame propagation, to the steady combustion; (2) the auto-ignition could occur in the thermal boundary layer and in the recirculation zone ahead of the injector, and the static temperature of inlet air flow is a decisive factor that effects the flame propagation from recirculation zone to the main flow; (3) the hydrogen stream behind the injector is parallel to the air flow, and there is strong turbulent mixing and reacting layer between them, while the supersonic combustion efficiency is decided mainly by their mixing efficiency.