基于SPH方法水滴撞击恒温壁面流动与换热的研究

Study on flow and heat transfer of droplet impacting on constant temperature surface in terms of smoothed particle hydrodynamics method

基于连续表面张力模型,提出了一种液滴和壁面表面张力的处理方法,结合光滑粒子流体动力学方法,建立了模拟大密度差表面张力问题的SPH算法。通过模拟水滴撞击壁面后的运动过程,与实验结果进行对比,验证了算法的有效性。应用该方法,先后模拟了单个低温大水滴,以不同直径和不同速度,撞击不同表面接触特性恒温壁面的运动过程。结果表明:当壁面的接触角在一定范围内,水滴的吸热率随接触角的增大而减小;而水滴的吸热率随着撞击速度和初始直径的增大均增大。

A new method of handling the surface tension of droplet and wall surface was established based on continuum surface force. The SPH algorithm was developed to simulate the surface tension problem with large density difference combined with Smoothed Particle Hydrodynamics method. The effectiveness of the algorithm was verified by comparing the simulation results with the experimental results. The impacting process of single low temperature droplet was simu- lated by this method with various diameter~ velocity and surface contact characteristics. The results showed that the heat absorption rate of water droplets decreased with the contact angle increasing in a certain rang while increased with the increase of impact velocity and initial diameter.