基于壁面吹气的高超声速湍流边界层减阻降热OA

Hypersonic vehicles are subjected to severe aerodynamic drag and thermal loads during practical flight.To address the issues of high skin-friction drag and intense aerodynamic heating under hypersonic turbulent boundary layer conditions,Large Eddy Simulation(LES)is performed to investigate the drag-and heat-reduction effects of wall micro-blowing through small pores on a Mach number of 6 flat-plate turbulent boundary layer.By comparing smooth-wall and porous-wall configurations,the streamwise distributions of the skin-friction coefficient and wall temperature are analyzed.The results show that wall micro-blowing can simultaneously reduce skin-friction drag and wall thermal load,with the maximum local drag-reduction and heat-reduction rates reaching 17.8%and 7.6%,respectively.Further analysis of the flow-control mechanisms reveals that micro-blowing lifts the mean velocity profile of the turbulent bound-ary layer,redistributes near-wall low-speed fluid toward the outer region,and is accompanied by enhanced stream-wise velocity fluctuations and shear Reynolds stress.Turbulence statistics indicate that micro-blowing intensifies the in-termittency of near-wall turbulence,increases the occurrence probability of ejection events,and strengthens the out-ward transport of low-momentum fluid,which contributes to drag reduction while effectively alleviating wall heat load.These results demonstrate that micro-blowing through small pores has promising potential for simultaneous drag and heat reduction in hypersonic turbulent boundary layers.