Direct Numerical Simulation On Wall-temperature Effect Of Shock Wave/Turbulent Boundary Layer Interaction

Shock wave/boundary layer interaction(SWBLI),as a typical phenomenon in supersonic and hypersonic flow field,has a great impact on the performance of hypersonic aircrafts.In real flight process,the wall temperature of aircrafts differs.And the aircrafts' wall temperatures in wind tunnel are also different from that in the flight process.It is of great importance to investigate the wall temperature effect of SWBLI flow field.This thesis concentrates on SWBLI flow field with direct numerical simulation to research on the wall temperature effect.Turbulent boundary layers on flats in different wall temperatures are first simulated and analyzed.The variety law of average velocity profile and friction coefficient affected by wall temperature is demonstated.And the performance of near-wall velocity-streaks in different wall temperatures is obtained.Furthermore,the way how wall temperature affect the characteristics of turbulent boundary layer is analyzed by the contrast of Reynold stress.Based on the research of wall temperature effect on turbulent boundary layer,the wall temperature effect on SWBLI flow filed is then investigated.The flow structure and statistical characteristics are analyzed.The way how near-wall streaks,coherent vortex,and turbulent kinetic energy change after the shock wave is demonstrated.On this basis,the differences of SWBLI flow field in different wall temperatures are summarized,including the separation zone scale,near-wall streaks,vortex structure and so on.SWBLI flow fields with diferent incident shock wave are simulated to obtain the flow characteristics affected by strength of incident shock wave.In addition,SWBLI flow fields with different incident shock wave and different wall temperature are compared,including pressure profile,turbulent kinetic energy profile and so on,to research into how wall temperature influence SWBLI flow field.It is testified that different wall temperatures,while having little direct influence on SWBLI flow field,result in different turbulent boundary layer,and then change characteristics of SWBLI floe field indirctly by the interaction of new turbulent boundary layers with shock wave.In the end,the features of SWBLI flow field affected by the strength of both wall temperature and incident shock wave are sum up.