中文摘要：

在喷雾冷却过程中，液滴撞击对壁面薄液膜的流动与换热特性有重要影响。本文采用Volume-of-Fluid（VOF）方法，对单液滴与双液滴撞击恒温壁面上薄液膜的换热特性进行了数值模拟分析。结果表明，液滴冲撞作用会使壁面产生很大热流，液滴初始直径越大、速度越快，换热系数越大。对于多液滴，撞击产生的扰动可以彼此迭加，从而进一步增强换热。

英文摘要：

The effect of micro-droplet impact plays an important role in the flow and heat transfer of the thin liquid film on a hot surface during spray cooling. The heat transfer characteristics of single and double droplets impacting a thin liquid film are numerical simulated using the Volume of Fluid （VOF） Method. The results indicate that the droplet impact leads to high heat flux. The surface heat transfer coefficient improves with the increase of droplet size and velocity. The disturbance caused by the impact can be superposed with each other to enhance the heat transfer effect.