Based on the Open FOAM code, droplet deformation and breakup were studied numerically with a simple coupled volume-of-fluid (VOF) and level-set (LS) model (S-CLSVOF) .By using the adaptive mesh refinement (AMR) technique, the interface capturing capability was improved, and computational cost was largely reduced.Firstly, the effects of We number on the drag coefficient and droplet shape were explored based on the numerical methods.Results indicate that droplets successively breakup into cap, capet, and cap/filament structures along with the increasing of We numbers.Secondly, the critical We numbers of bag breakup under a wide Ohnesorge range of (0.001, 2.000) were investigated, and the theoretical model was improved based on the numerical results and the Rayleigh-Taylor instability.Finally, breakup under the interaction between droplet pairs was studied.Results indicate that the competition/coalescence of recirculation restrains/promotes the droplet deformation and breakup, respectively.%基于Open FOAM, 采用简化耦合的多相流模型 (S-CLSVOF) 对液滴破碎进行了数值模拟研究.自适应网格加密 (AMR) 技术的应用提高了界面捕捉能力, 同时减低了计算成本.基于该数值方法, 首先考察了We数对液滴拽力系数和破碎形态的影响.结果表明:We数并不影响变形初期的拽力系数;随着We数增加, 破碎液滴依次呈现帽状、帽状/液网及帽状/液丝结构.其次, 研究了宽Ohnesorge数 (0.0012.000) 范围内的袋式破碎临界We数, 并基于模拟结果和Rayleigh-Taylor不稳定性, 改进了袋式破碎临界We数的理论预测模型.最后, 考察了液滴对相互作用下的破碎, 结果表明, 回流区的竞争/融合分别抑制/促进液滴对的变形与破碎.
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