Reducing skin friction by boundary layer combustion on a generic scramjet model
Combustion of hydrogen in the boundary layer of a simplified scramjet model is investigated. The analytical model for combustion is introduced for a flat plate in a turbulent boundary layer. Investigations are carried out for a fixed scramjet geometry and Mach 10 at 36 km altitude. Fuel is injected in the combustor as well as into the boundary layers of the inlet and the combustor. The amount of fuel injected at each location is varied but the overall fuel flowrate is kept constant for an equivalence ratio of one. The results show an optimum ratio between the fuel injected into the boundary layers and the fuel in the combustor. The specific impulse of the scramjet model considered is increased by 12%.
KeywordsBoundary Layer Mass Flow Rate Skin Friction Flat Plate Turbulent Boundary Layer
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