AI 中文总结
本文针对现有三相EHD模型缺乏热力学一致性的问题，基于Onsager变分原理提出热力学一致的三相EHD模型，结合格子玻尔兹曼方法开发数值框架，经多基准案例验证后用于模拟液滴在电场及复合流场中的动力学行为，提供了可靠的多相EHD数值工具。
AI 中文摘要
多相电流体动力学（EHD）流动在各类工程应用中发挥关键作用。然而，现有针对三相电流体系统的数值研究主要依赖现象学模型，往往忽略热力学一致性及关键的表面电荷对流机制。为解决这些基础缺陷，本文提出一种严格基于Onsager变分原理推导的、热力学一致的三相EHD模型。该理论框架从本质上保证了热力学一致性，且无需先验假设即可准确捕捉复杂的多物理场相互作用。此外，本文开发了一种介观格子玻尔兹曼方法来求解所提模型，该方法可自然捕捉界面演化与电荷输运。通过多个基准案例对该数值框架的精度进行了严格验证，包括微通道中的电渗流、三相液体透镜的铺展、静态复合液滴的平衡，以及均匀电场下复合液滴的变形。利用该已验证的框架，本文研究了EHD应用，具体模拟了电场下双液滴的聚结与分离的复杂动力学，以及受EHD与剪切流共同作用的液滴行为。总体而言，本工作为探索多相EHD系统的高度非线性行为提供了一种鲁棒、热力学可靠的数值工具。
英文摘要
Multiphase electrohydrodynamic (EHD) flows play a crucial role in various engineering applications. However, existing numerical studies on three-phase electrohydrodynamic systems predominantly rely on phenomenological models, often neglecting thermodynamic consistency and critical surface charge convection mechanisms. To address these fundamental gaps, this paper proposes a thermodynamically consistent three-phase EHD model derived strictly from the Onsager variational principle. This theoretical framework intrinsically guarantees thermodynamic consistency and accurately captures complex multiphysics interactions without requiring a priori assumptions. Furthermore, a mesoscopic lattice Boltzmann method is developed to solve the proposed model, enabling the natural capture of interfacial evolution and charge transport. The accuracy of the numerical framework are rigorously validated against several benchmark cases, including electroosmotic flow in microchannels, the spreading of a three-phase liquid lens, the equilibrium of static compound droplet, and the deformation of compound droplet under uniform electric field. Using this validated framework, we investigate EHD applications, specifically simulating the complex dynamics of double droplet coalescence and separation under electric field, as well as the behavior of droplets subjected to combined EHD and shear flow. Overall, this work provides a robust, thermodynamically reliable numerical tool for exploring the highly nonlinear behaviors of multiphase EHD systems.
