Frequency and Heated Region Shape Effects on the Physics of Mach 2 Flow Over a Hemisphere Cylinder

The interaction of a heated region with a hemisphere cylinder in Mach 2 flow is numerically investigated. Energy deposition is applied at frequencies of 4148.86 Hz and 8297.72 Hz (i.e. Strouhal number of 0.2 and 0.4 respectively) for two heated region shapes, a spherical heated region and a truncated cone heated region. Details of how the flow physics changes and its effect on drag reduction are included. Changing the heated region shape, alters blast wave shape and vortex formation processes. For single impulse energy deposition, the truncated cone accounts for more drag reduction compared to the spherical heated region. Pulsed energy deposition results in an increase in the drag reduction obtained.