Effect of Transverse Hydrogen Injection on Cooling of Hypersonic Vehicle Surfaces

A study was made of a scramjet inlet to determine the effects of injecting hydrogen fuel on convective heat transfer. This work is part of a research effort to simulate transverse gas injection into supersonic airstreams, using a computer code that solves the Navier-Stokes equations, with both laminar and turbulent flow schemes, fully coupled with a multi-species, multi-equation kinetics reaction model. Slot fuel injection is modeled at various hydrogen jet conditions and different injection angles. Results from this study suggest that premixing fuel and air at the inlet of a scramjet engine, if properly controlled, can reduce the heat transfer to the inlet surfaces. Other effects of transverse fuel injection such as ignition potential and flow separation were also investigated. List of Symbols CH wall heat transfer coefficient d slot size h height of computational domain H2 hydrogen fuel L length of computational domain m mass flow P gas pressure Pr Prandtl Number q heat flux T gas temperature U streamwise velocity u,v cartesian velocity components x,y cartesian coordinates 8 boundary layer thickness K coef. of thermal conductivity p gas density 0H2 equivalence ratio for cooling Subscripts oo inlet air conditions a air aw adiabatic wall f fuel w wall 1