ANALYSIS OF EXTERNAL BURNING ON INCLINED SURFACES IN SUPERSONIC-FLOW

An earlier analysis of a viscous mixing region with heat addition inte racting with a supersonic external flow has been extended to include c ases with a sloped wall beneath the viscous region. Also, cases with a supersonic to subsonic transition at the viscous throat have been stu died for the first time. Limitations on the allowable heating value of the fuel that correspond to smooth subsonic to supersonic, or superso nic to subsonic transitions, are delineated and explained. The effects of wall slope at the throat and external Mach number on these limitat ions are shown. The results of calculations for representative cases s how that it is possible to cancel base drag and even produce net thrus t for cases with downward sloped walls if the initial Mach number in t he viscous zone is supersonic prior to addition of heat. This correspo nds to a supersonic to subsonic transition. For an initially subsonic flow, the results indicate pressures below the freestream static press ure throughout the flowfield. This means that only very limited drag f rom nameholders, such that the flow remains supersonic before heat add ition, are advisable. Finally, some directions for future work are out lined.