液滴撞击低温超疏水表面运动状态的数值模拟研究

Numerical simulation of motion state of droplets impacting the superhydrophobic cold surface

中文关键词: 液滴  超疏水冷表面  表面温度  反弹  黏附

英文关键词: droplet  superhydrophobic cold surface  surface temperature  rebound  adhere

中文摘要:

      本文针对液滴撞击固体表面后出现的反弹和黏附两种运动状态，通过引入基于连续温度函数的能量方程，建立了用于计算液滴运动、传热和相变过程的数值模型，并与实验结果对比，验证了数值模型的准确性。进而模拟了具有不同韦伯数We和奥内佐格数Oh的液滴撞击低温超疏水表面的运动、传热和相变过程。结果表明：液滴撞击后的运动状态主要取决于奥内佐格数Oh，临界范围是0.022-0.026，而基本不受韦伯数We的影响。当液滴撞击后的运动状态为反弹时，韦伯数We越大的液滴，最大铺展直径越大。而当韦伯数相同时，随着奥内佐格数Oh的增大，液滴与表面的接触时间越大。

英文摘要:

      In this paper, the motion state including rebound and adsorption of droplets impacting on solid surfaces were studied. The numerical model for calculating droplet motion, heat transfer and phase change process was established by introducing the continuous energy equation. Then the accuracy of the model was verified by compared with the experimental results. Finally the processes of droplets with various We and Oh numbers impacting on the super hydrophobic surfaces with various temperatures. The results show that the response behavior of droplet after impacting surface is mainly decided by the Ohnesorge number in the range from 0.022 to 0.026, while has little relationship with We number. When the response behavior of droplets is rebound, the larger We number would cause a larger maximum spreading diameter. For the same We number, the contact time of the droplet and the surface increases with the increase of Oh number.