Investigation of Boundary Layer and Performance Effects of Transpiration CoolingThrough a Porous Plate in a Rocket Nozzle

摘要

This study used a range of low blowing ratios with air through an area of porousmaterial in a Mach 2.0 nozzle to quantity the change in boundary layer thickness as a function of blowing ratio. Also, exit and wall Mach number profiles at each blowing ratio were collected to characterize performance losses as a result of blowing. Performance in terms of specific impulse was also studied. As expected, the boundary layer thickness increased and nozzle performance in terms of exit Mach number decreased with increasing blowing ratio.