Detached-eddy simulation of supersonic flow past a spike-tipped blunt nose  

作　　者：Yuan XUE Liang WANG Song FU 

机构地区：[1]School of Aerospace Engineering,Tsinghua University

出　　处：《Chinese Journal of Aeronautics》2018年第9期1815-1821,共7页中国航空学报（英文版）

基　　金：funded by the National Natural Science Foundation of China(Nos.11572177,11572176,51376106 and 11272183);the Tsinghua University Initiative Scientific Research Program of China(No.2014z21020)

摘　　要：Space vehicle in atmosphere travels mostly at supersonic speed and generates a very strong bow shockwave around its blunt nose. Oblique shock and conical separated flow zone generated by a forward disk-tip spike significantly reduce the drag by reducing the high pressure area on the blunt nose. This study employs improved delayed detached eddy simulation to investigate the characteristic flow structures around a spike-tipped blunt nose at Mach number of 3 and Reynolds number（based on the blunt-body diameter） of 2.72x10;. The calculated time-averaged quantities agree well with experimental data. Characteristic frequencies in different flow regions are extracted using fast Fourier transform. It is found that two distinct instability modes exist: oscillation mode and pulsation mode. The former is related to the foreshock/turbulence interaction with nondimensional frequency at around 0.004. The latter corresponds to the interaction between turbulence and shock structures around the blunt nose, with a typical coherent structure shedding frequency at 0.092.Space vehicle in atmosphere travels mostly at supersonic speed and generates a very strong bow shockwave around its blunt nose. Oblique shock and conical separated flow zone generated by a forward disk-tip spike significantly reduce the drag by reducing the high pressure area on the blunt nose. This study employs improved delayed detached eddy simulation to investigate the characteristic flow structures around a spike-tipped blunt nose at Mach number of 3 and Reynolds number(based on the blunt-body diameter) of 2.72x10^8. The calculated time-averaged quantities agree well with experimental data. Characteristic frequencies in different flow regions are extracted using fast Fourier transform. It is found that two distinct instability modes exist: oscillation mode and pulsation mode. The former is related to the foreshock/turbulence interaction with nondimensional frequency at around 0.004. The latter corresponds to the interaction between turbulence and shock structures around the blunt nose, with a typical coherent structure shedding frequency at 0.092.

关 键 词：Detached-eddy simulation Drag reduction Oscillation mode Pulsation mode Spike-tipped blunt vehicle Supersonic flow 

分 类 号：V211[航空宇航科学与技术—航空宇航推进理论与工程] V411