基于格子Boltzmann方法的液滴沿固壁铺展动态过程模拟

矿井喷雾降尘是利用水雾使粉尘润湿沉降的过程，考虑到固体与液体间分子作用力，本文采用格子Boltzmann方法对液滴沿固壁铺展的动力学行为进行了数值模拟，结果发现铺展直径及动态接触角随时间呈指数规律，确定了液滴表面张力与铺展最大直径间的关系，固壁润湿性对铺展最大速度值影响较大，这些与物理试验及文献结果符合良好. 进一步考察了疏水性强的固壁，发现当液滴表面张力足够小时，铺展接触角可以在90°以下，与理论公式符合. 研究发现铺展过程中伴随着振荡，且铺展到最大时液膜有回缩趋势. 关键词： 液滴 格子Boltzmann方法 铺展 数值模拟

Dynamic process simulation of droplet spreading on solid surface by lattic Boltzmann method

Spray dust mechanism is to use spray to wet and reduce the coal mine dust. Based on lattice Boltzmann method, the dynamic behaviors of droplet spreading on solid surface are simulated numerically in consideration of the molecules reaction between fluid and solid. Results show that the spreading diameter and dynamic contact angle change exponentially with time. The relationship between droplet surface tension and maximum spreading diameter is determined; it is shown that the wettability of solid surface has a great influence on the maximum spreading velocity. All the above numerical results are in good agreement with the experimental and theoretical results reported in the literature. Moreover, the solid surface with high hydrophobicity is further investigated. It is found that the spreading contact angle can be less than 90° if the droplet surface tension is small enough, which agrees well with the theoretical formula. The simulation also shows that there occurs oscillations in the spreading process and retraction when the droplet spreads to its maximum.
Keywords： droplet lattic Boltzmann method spread numerical simulation