On the drag reduction mechanism of hypersonic turbulent boundary layers subject to heated wall blowing  

作　　者：Qiang Liu Zhenbing Luo Yan Zhou Wei Xie Siwei Dong 

机构地区：[1]College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China [2]State Key Laboratory of Aerodynamics,Mianyang 621000,China

出　　处：《Advances in Aerodynamics》2023年第1期126-148,共23页空气动力学进展（英文）

基　　金：the National Natural Science Foundation of China(Grant Nos.12202488 and 12072306);Natural Science Program of NUDT(ZK22-30);Independent Cultivation Project for Young Talents of the College of Aerospace Science and Engineering.

摘　　要：Turbulence drag reduction is of great significance for the range increase of hypersonic flight vehicles.The proposed velocity-temperature coupling control method(Liu et al,Phys Rev Fluids 6:044603,2021)is further extended to the hypersonic turbulent boundary layer.Direct numerical simulation results of four comparative cases show that the heated wall blowing achieves a drag reduction rate of 10.58%,which is about the sum of wall blowing(5.27%)and wall heating(6.35%).By evaluating the control efficiency,however,it is found that heated wall blowing is not as good as wall blowing and cannot obtain net energy saving rate.The modified FIK decompositions of skin friction coefficient indicate that the cliffy decrease of the mean convection term is the primary contribution for the drag reduction.Effects of the proposed control measure on turbu-lence statistics and coherent structures are also analyzed.Streamwise vortex is found to be away from the wall,thus leading to a lower friction drag.

关 键 词：Hypersonic turbulent boundary layer Turbulence drag reduction Velocity-temperature coupled control Turbulence statistics Turbulence structures Direct numerical simulations 

分 类 号：O35[理学—流体力学]