Impact of free-stream disturbances on blunt body aerothermodynamics in hypersonic flow

Abstract

The study investigates the effects of freestream disturbances (acoustic, vortical and entropy) on wall pressure and wall heat flux in front of double cone geometry in hypersonic flow. The two double cone geometries with small cone angle and high cone angles are simulated at hypersonic Mach 6 by using 2D-axisymmetric Navier Stokes Laminar flow solver, exhibit ing steady and oscillatory flow behaviour with constant inlet boundary, respectively. The acoustic (fast and slow wave), vortical and entropy disturbances with single frequency of 20 kHz and amplitude upto 1% are modelled as time-dependent inlet boundary and are introduced after achieving solutions for both cases of double-cone geometries after 5ms. The impact of these freestream disturbances was estimated by analyzing the wall pressure and wall heat flux fluctuations and it was found that rms of wall pressure fluctuation increases approxi mately 10 time and wall heat flux fluctuation increases 6 times for high angled double cone geometry, when compared to small angle double cone geometry subjected to same level of freestream disturbances.