Hu Qingming, Hu Fengshi, Xu Donghui, Zhang Kailiang
School of Mechtranoics Engineering, Qiqihar University, Qiqihaer 161006, China.
The Engineering Technology Research Center for Precision Manufacturing Equipment and Industrial Perception of Heilongjiang Province, Qiqihar University, Qiqihaer 161006, China.
Micromachines (Basel). 2023 Apr 27;14(5):951. doi: 10.3390/mi14050951.
In this work, we establish a two-dimensional axisymmetric simulation model to numerically study the impacting behaviors between oil droplets and an immiscible aqueous solution based on the three-phase field method. The numerical model is established by using the commercial software of COMSOL Multiphysics first and then validated by comparing the numerical results with the previous experimental study. The simulation results show that under the impact of oil droplets, a crater will form on the surface of the aqueous solution, which firstly expands and then collapses with the transfer and dissipation of kinetic energy of this three-phase system. As for the droplet, it flattens, spreads, stretches, or immerses on the crater surface and finally achieves an equilibrium state at the gas-liquid interface after experiencing several sinking-bouncing circles. The impacting velocity, fluid density, viscosity, interfacial tension, droplet size, and the property of non-Newtonian fluids all play important roles in the impact between oil droplets and aqueous solution. The conclusions can help to cognize the mechanism of droplet impact on an immiscible fluid and provide useful guidelines for those applications concerning droplet impact.
在这项工作中，我们基于三相场方法建立了一个二维轴对称模拟模型，以数值研究油滴与不混溶水溶液之间的碰撞行为。数值模型首先使用商业软件COMSOL Multiphysics建立，然后通过将数值结果与先前的实验研究进行比较来进行验证。模拟结果表明，在油滴的冲击下，水溶液表面会形成一个弹坑，该弹坑会随着该三相系统动能的转移和耗散而先扩张后坍塌。对于液滴，它会在弹坑表面变平、铺展、拉伸或浸入，并且在经历几次下沉-反弹循环后最终在气液界面达到平衡状态。冲击速度、流体密度、粘度、界面张力、液滴大小以及非牛顿流体的性质在油滴与水溶液的碰撞中都起着重要作用。这些结论有助于认识液滴对不混溶流体的冲击机理，并为那些涉及液滴冲击的应用提供有用的指导。
