Hypersonic interference heating in the vicinity of surface protuberances

摘要

The understanding of the behaviour of the flow around surface protuberances inhypersonic vehicles is developed and an engineering approach to predict thelocation and magnitude of the highest heat transfer rates in their vicinity ispresented. To this end, an experimental investigation was performed in ahypersonic facility at freestream Mach numbers of 8.2 and 12.3 and Reynoldsnumbers ranging from Re (a)/m = 3.35 x 10(6) to Re (a)/m = 9.35 x 10(6). Theeffects of protuberance geometry, boundary layer state, freestream Reynoldsnumber and freestream Mach numbers were assessed based on thin-film heattransfer measurements. Further understanding of the flowfield was obtainedthrough oil-dot visualizations and high-speed schlieren videos. The localinterference interaction was shown to be strongly 3-D and to be dominated by theincipient separation angle induced by the protuberance. In interactions in whichthe incoming boundary layer remains unseparated upstream of the protuberance,the highest heating occurs adjacent to the device. In interactions in which theincoming boundary layer is fully separated ahead of the protuberance, thehighest heating generally occurs on the surface just upstream of it except forlow-deflection protuberances under low Reynolds freestream flow conditions inwhich case the heat flux to the side is greater.