高超音速流场测量是研制空天飞机、高超音速飞行器、巡航弹道导弹等国家重大战略装备的基础，粒子图像测速（Particle image velocimetry，简称PIV测量）是高超音速流场的全场非接触测量的有效方法，粒子示踪机理是影响高超音速流场PIV测量精度的最为关键因素。现有低速粒子的示踪机理无法适用于高超音速、非定常、高度非均匀流场的PIV高精度测量，已成为制约我国高性能PIV测量仪器自主研发的瓶颈。本项目拟建立高温、高压、高超音速状态下粒子的动力学和光散射性模型，提出粒子流动跟随性与可测量性的判断依据，揭示高超音速流场PIV测量粒子示踪机理，综合优化设计粒子的形状、尺寸、材料和密度等参数，研究纳米级固体示踪粒子可制造性，提升高超音速流场PIV测量精度，在空天飞机、高超音速飞行器等重大战略装备风洞试验的高超音速流场PIV测量中验证应用，具有十分重要的理论意义和应用价值。

Particle image velocimetry (PIV) for hypersonic flow measurement is a basis measurement technology for developing significant aerospace equipments, such as space planes, hypersonic aircraft, cruise missile and so on. Particles tracer mechanism is the most important factor that affects the precision of PIV measurement of hypersonic flow. The present existing particle tracking mechanism for low-speed flow can not be applied to PIV measurement of hypersonic flow, due to the unsteady, highly non-uniform flow dynamics. And this has become a theory bottleneck of independent research and development of significant aerospace equipment in our country. In this study, we intend to establish the dynamic model and light scattering model of particles in high-temperature, high-pressure, hypersonic flow, try to propose novel criterions of particle tracking characteristics and particle measurability. Then, the theory of particle tracking mechanism of PIV measurements of hypersonic flow will be established. The shape, size, material and density parameters of tracer particles will be designed by using modern optimization theory, and a new kind nanoscale solid tracer particle will be manufactured in order to apply it for PIV measurements of hypersonic flow in practical applications, such as wind tunnel tests of space plane, hypersonic aircraft and so on . This study has a very important theoretical significance and application value.