Transpiration Cooling Experiment for Scramjet Engine Combustion Chamber by High Heat Fluxes

A transpiration cooling experiment using an optical heating method that provided a heat flux as high as 234 W/cm 2 on the surface of specimen for a scramjet engine was performed. In this experiment, 19-mm-diam sintered, powdered, stainless-steel tubes and a 25-mm square cross-sectional tube of perforated Inconel tube were used to investigate transpiration cooling effectiveness. The cooling effectiveness by transpiration for each specimen was measured and analyzed. As a result, the transpiration cooling mechanism appeared to be a promising approach to remove a large amount of heat from the engine wall. A preliminary analysis of the transpiration cooling mechanism and a scaling conversion study that translates the results from helium tests into the case when a hydrogen medium is used are included.