Effects of blunt trailing edge flow discharge in supersonic regime

Flow discharge at the blunt trailing edge of bodies immersed into supersonic stream alters significantly the downstream aerodynamic characteristics. This paper studies the changes in the base region topology for a wide range of purge ejection, using Unsteady Reynolds Averaged Navier-Stokes solutions. At low purge rate the base pressure increases, resulting in a reduction of the trailing edge shock wave intensity. Supersonic purge flows diminishes the base pressure and thus strengthens the shock wave, a linear relationship between the base pressure and the shock strength was obtained for the investigated conditions. Furthermore, an auxiliary shock wave system was observed to form upstream of the main fish tail shock at certain discharge rates.