高速流动中PIV示踪粒子松弛特性研究

示踪粒子的随流能力是PIV技术在高速流动中应用的关键点之一。在上海交通大学变马赫数高速风洞中开展了PIV实验研究，重点提出一种评价示踪粒子随流能力的松弛特性分析模型。在马赫数4条件下尖锥、尖劈等模型PIV实验研究中，可以准确分析粒子的松弛特性，粒径分析结果与实验吻合较好，并验证了高速流动PIv的测试精度和示踪粒子布撒能力。

Research on the relaxation characteristics of PIV tracer particles in supersonic flow

The tracking capability of tracer particles is one of the key points to the applications of PIV technique in supersonic flow. In this paper, the experiment research of PIV technique was developed in Multi-Mach number High-speed Wind Tunnel of SJTU, and an analytical model of relaxation characteristics was specially proposed, which used to evaluate the tracking capability of tracer particles. In the supersonic flow of Ma4, the results of the PIV experiments on typical models, including a sharp cone and two wedges with different semiapex angles, agree well with the analytical results of the particle diameters, and demonstrate the measurement accuracy and the seeding efficiency of PIV in the supersonic flow. It indicates that the proposed model is prac- tically credible to analyze the relaxation characteristics of tracer particles.