壁面渗透气膜工质对圆锥高超声速边界层稳定性的影响  

Effect of wall-seeping gas film under different working media on stability of conical hypersonic boundary layer

作　　者：胡玉发 易仕和[1] 刘小林 徐席旺 张震 张臻 Hu Yu-Fa;Yi Shi-He;Liu Xiao-Lin;Xu Xi-Wang;Zhang Zhen;Zhang Zhen(College of Aerospace Science and Engineering,National University of Defense Technology,Changsha 410073,China)

机构地区：[1]国防科技大学空天科学学院,长沙410073

出　　处：《物理学报》2024年第12期221-234,共14页Acta Physica Sinica

摘　　要：壁面渗透气膜是一种有应用前景的高超声速边界层转捩控制和减阻降热方式.在马赫数6高超声速静音风洞内,使用纳米粒子示踪的平面激光散射(nano-tracer planar laser scattering,NPLS)技术和高频脉动压力测试技术,研究了壁面渗透气膜工质(氦气、空气和二氧化碳)在相同体积流量条件下对圆锥高超声速边界层的影响.实验结果表明,壁面渗透气膜显著增厚了边界层,最厚位置都出现在渗透区域下游边界处,且氦气气膜时边界层最薄,二氧化碳气膜时最厚.通常,空气气膜和二氧化碳气膜使得边界层内提前出现规则的绳状交织的第二模态波结构,但体积流量较大条件下二氧化碳气膜时,扰动波结构类似剪切层不稳定性.氦气气膜时,扰动波结构不是第二模态波,其形状不规则,随时空变化较大,壁面脉动压力功率谱密度没有出现峰值频率.空气气膜时第二模态波波长大约是边界层厚度的2—3倍,而二氧化碳气膜时增大到3倍以上.二氧化碳气膜时第二模态波峰值频率最小,频带范围最窄,波长最长,幅值最大,扰动波传播距离较远且非线性相互作用较强.Wall-seeping gas film(WSGF)is a promising method of controlling hypersonic boundary layer transition and reducing friction drag and heat transfer.Experiments are conducted in a Mach 6 hypersonic quiet wind tunnel by using nano-tracer planar laser scattering(NPLS)and high-frequency fluctuating pressure measuring technique.This work investigates the effects of wall-seeping helium,air,and carbon dioxide gas films under identical volume flow rate condition on conical boundary layer thickness,disturbance wave structure,wavelength,frequency,amplitude,and nonlinear interaction.The experimental results reveal that the WSGF significantly thickens the hypersonic boundary layer,with the thickest position appearing at the downstream boundary of the seeping zone.The boundary layer thickness is thinnest for helium gas film but thickest for carbon dioxide gas film.Generally,air gas film and carbon dioxide gas film induce the regular,rope-like,and interlaced second-mode waves to appear in advance in the boundary layer.However,under a higher volume flow rate for carbon dioxide gas film,the disturbance wave structure resembles interface fluctuations,with a characteristic wavelength of approximately 18 mm and a peak frequency as low as about 35 kHz,but no the rope-like interlaced characteristic.At this time,the influence of shear layer instability becomes significant.The disturbance waves do not exhibit second-mode wave characteristics for wall-seeping helium gas film,whose shape is irregular and undergoes deformation with time and space.Additionally,the power spectral density of wall fluctuating pressure exhibits insignificant variation with volume flow rate and flow direction,which is similar to the characteristic of power spectral density in the laminar boundary layer and has no peak frequency.The wavelength of second-mode waves is about 2-3 times the boundary layer thickness for air gas film,and increases to more than 3 times for carbon dioxide gas film.The application of carbon dioxide gas film results in smaller peak frequenc

关 键 词：高超声速边界层 壁面渗透气膜 第二模态波 剪切层不稳定性 

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