基于格子玻尔兹曼方法（Lattice Boltzmann Method, LBM）对固着在加热基板上的液滴铺展及蒸发过程进行模拟,主要研究重力场、基板润湿性以及初始环境温度对液滴铺展及蒸发过程的影响。通过预测蒸发过程中液滴与基板的接触直径变化和液滴剩余质量变化,分析液滴形状及体积变化。研究结果发现,液滴形貌及蒸发过程受重力影响较大,重力作用下液滴铺展现象明显且蒸发加快。基板的接触角越小,液滴铺展现象越明显,其接触直径越大,蒸发越快。当环境温度与基板温度相差较大时,液滴内部出现涡流,强化换热使蒸发过程加快。
Based on the Lattice Boltzmann Method (LBM), this paper simulated the droplet evaporation process sessile on the heated substrate, mainly exploring the influence of the actual gravity field, the substrate wettability and the initial environmental temperature field on the droplet evaporation. The flow and heat transfer of droplet were analyzed by the instantaneous evolution and internal velocity distribution of droplet. The shape and volume of droplet were analyzed by calculating the change of contact diameter and residual mass of droplet. The results show that the droplet evaporation process is greatly affected by gravity, and the droplet spreading phenomenon is obvious and evaporation is accelerated under the action of gravity. The smaller the contact angle of substrates, the more obvious the droplet spreading, the larger the contact diameter and the faster the evaporation. When the environmental temperature was quite different from that of the substrate, eddy current appears in the droplet, which intensifies the heat transfer and accelerates the evaporation process.
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