PSP Measurements of Supersonic Flow Across an Open Cavity with Serrations

Abstract

*† ‡ An experimental investigation was conducted to determine the effect of adding serrated edges to straight cavities at a freestream Mach number of 2. The investigation used pressure sensitive paint (PSP) and unsteady pressure measurements to investigate the cavity flow field. The length to depth ratio (l/d) of the cavity was 8. This paper describes the PSP measurements, which were conducted for a range of Reynolds numbers for both straight edge cavities and those with the addition of serrations to the leading and trailing edges. The experimental technique, which used commercial PSPs and in-situ calibrations to account for spatial non-uniformities in illumination and temporal non-uniformities in surface temperature, is described in detail. While subtle differences were observed in the cavity flow field and in the measured surface pressure distributions, the leading and trailing edge modifications were not observed to have a significant effect.