高超声速边界层流动稳定性实验研究

高超声速条件下边界层转捩相关研究是近年来空气动力学领域的研究热点。通过采用基于纳米粒子示踪平面激光散射(Nano-tracer-based planar laser scattering,NPLS)技术以及温敏漆等测试技术,对高超声速边界层的流动稳定性开展了实验研究。通过NPLS技术,对圆锥边界层中第二模态波精细结构进行了测量,并基于时间相关的测量结果,对第二模态波的波长和频率进行了分析。针对裙锥边界层NPLS结果,计算了特定位置上功率谱空间分布结果,测量得到了高次谐波成分。通过温敏漆和NPLS结果,发现主导三角翼前缘边界层转捩的模态为行进横流模态,分析了该模态的特性,并且与Kulite传感器测量得到的频率进行比较。

Experimental study on flow stability of hypersonic boundary layer

Research on hypersonic boundary layer transition is a hot topic in the field of aerodynamics in recent years.The flow stability of hypersonic boundary layer was experimentally studied by the Nano-tracer-based planar laser scattering(NPLS)technique and temperaturesensitive paints technique.Through the flow visualization experiments,the fine structure of the rope-like second mode wave in the conical boundary layer was measured,and the wavelength and frequency of the second mode wave were analyzed based on the temporal-correlated NPLS results.Compared with the boundary layer on the straight cone,the second mode wave on the flared cone is more obvious,and the evolution speed of the second mode wave is slower,so the fine second mode wave structure can be measured in a longer flow direction range.According to the NPLS results of flared-cone boundary layer,the spatial distribution results of power spectrum at specific positions were calculated,and the harmonic components were measured.Temperature-sensitive paints and flow visualization experiments indicated that the transition of the boundary layer near the edge of the delta wing was led by the traveling cross-flow mode,and the characteristics of this mode were consistent with the frequency measured by Kulite sensor.