Effects of freestream disturbances in front of spiked blunt nose at hypersonic flow

Abstract

The effects of high frequency slow and fast acoustic wave freestream disturbances are modelled in front of pulsating bow shock formed at spiked blunt nose in hypersonic flow. These disturbances are introduced as time-dependent inflow boundary condition with pressure fluctuation amplitudes of up to 1% at a single frequency of 20 kHz. In this study, initially spiked blunt nose exhibiting pulsating flow field in front of spiked blunt nose (L/D = 2) at hypersonic flow Mach 6, has been simulated by using 2D axisymmetric Navier Strokes Laminar solver. Different freestream disturbances are introduced after achieving self-sustainable pulsating flow and replaced with constant boundary condition after 2 ms. The stabilization of the large amplitude pulsations are observed by fast acoustic disturbances with pressure amplitude of more than 0.5% and & 1%, while slow acoustic wave disturbance can stabilize the pulsation only with 1% pressure fluctuations.