Improving the staircase approximation for wettability implementation of phase-field model: Part 2 - Three-component permeation
Improving the staircase approximation for wettability implementation of phase-field model: Part 2 - Three-component permeation
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DOI：
10.1016/j.camwa.2022.01.005
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发表时间：
2022-03
期刊：
影响因子：
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通讯作者：
A. Zarareh;Stephen B. Burnside;S. Khajepor;Baixin Chen
中科院分区：
文献类型：
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作者：
A. Zarareh;Stephen B. Burnside;S. Khajepor;Baixin Chen
本文采用文献[1]中提出的新的润湿边界处理方法，对复杂结构多孔介质中复合液滴的驱替动力学进行了数值研究。复合液滴由两种不混溶的流体组成，另一种流体包围形成三相系统。为了研究复合液滴在两种状态下的渗透和铺展，采用格子Boltzmann方法（LBM）求解了不同润湿性和控制无量纲数（包括雷诺数（25-100）、韦伯数（100-1000）和密度比（7.5-750））下的守恒相场模型。此外，每个液滴的渗透和蔓延，而不存在的其他在二元系统中，进行了比较与那些三元。结果表明，渗透的方式是由表面张力，润湿性和密度比的变化的影响完全取决于键数和毛细管或重力占主导地位的制度的值。此外，似乎在毛细作用占主导地位的制度，一个液滴的迁移模式不能独立于其他评估，因为影响的因素的毛细管压力和粘性耦合上的一个，影响渗透和传播的其他。最后，它是确定的，三元渗透是慢于二元和其他液滴的存在限制了在三元系统的早期阶段蔓延。
In this study, the displacement dynamics of compound droplet inside porous medium with complex structure is numerically investigated by the newly-proposed wetting boundary treatments in Part 1 [1]. The compound droplet consists of two immiscible fluids surrounded by another fluid forming a three-phase system. To investigate the compound droplet's penetration and spreading in two regimes, the conservative phase-field model is solved via the lattice Boltzmann method (LBM) at different wettability and governing non-dimensional numbers including the Reynolds number (25-100), Weber number (100-1000), and density ratio (7.5-750). Moreover, the permeation and spreading of each droplet, without the presence of the other in the binary system, is compared with those of ternary. It is revealed that the way the penetration is influenced by the variation of surface tension, wettability, and density ratio completely depends on the value of Bond number and the capillary or gravitational-dominant regimes. Furthermore, it appears that in the capillary-dominant regime, the migration pattern of one droplet cannot be evaluated independent of the other, since the factors affecting the capillary pressure and viscous coupling on one, affects the penetration and spreading of the other. Finally, it is identified that ternary penetration is slower than binary and the presence of the other droplet confines the early stage spreading in the ternary system.