高速撞壁液滴空化演化过程的数值模拟

Numerical Simulation on Cavity Evolution During High-speed Droplets Impingement on the Wall

本文针对高速液滴撞击刚性壁面后液滴内部出现的空化及其演化过程进行了数值模拟。采用考虑了快速相变机制的可压缩两相流模型,有效捕捉了高速(110 m/s)液滴撞壁过程中产生的撞壁激波,以及复杂激波的反射和膨胀波聚焦作用形成低压区并生成空化泡、空化泡被逐渐压缩直至最后溃灭并产生溃灭压力波的完整过程,整个过程与实验结果十分吻合。进一步,比较了速度对液滴撞壁过程的影响规律,发现撞壁初速度越高产生的空化泡越大.研究为深入理解高速撞壁的液滴动力学规律提供了理论依据。

In this work, a numerical investigation of high-speed droplet impingement on solid wall was carried out based on the compressible two-phase flow model considering the instanta- neous phase transition procedure. The results showed that a series of flow phenomena, including the impinging water hammer shock, the reflected rarefaction waves, and the cavity inception as well as its evolution, were well consistent with the experimental results of high-speed （110 m/s） droplet impingement. In addition, the droplet of higher initial speed （150 m/s） was further simulated to investigate the influence of initial impinging speed on the cavity evolution inside a droplet.