In this paper, an integrated smoothed particle hydrodynamics (SPH) model for complex interfacial flows with large density ratios is developed. The discrete continuity equation and acceleration equation are obtained by considering the time derivative of the volume of particle and Eckart's continuum Lagrangian equation. A continuum surface force model is used to meet the fact that surface force may not be distributed uniformly on each side of the interface. An improved boundary condition is imposed to model wall free‐slip and no‐slip condition for interfacial flows with large density ratios. Particle shifting algorithm (PSA) is added for interfacial flows by imposing the normal correction near the interface, called as Interface‐PSA. Then four representative numerical examples, including droplet deformation, Rayleigh‐Taylor instability, dam breaking, and bubble rising, are presented and compared well with reference data. It is demonstrated that inherent interfacial flow physics can be well captured, including surface tension and the dynamic evolution of the complex interfaces.

中文翻译：

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具有大密度比的复杂界面流动的集成平滑粒子流体动力学模型

本文建立了一种适用于大密度比的复杂界面流动的综合光滑粒子流体动力学模型。通过考虑粒子体积的时间导数和Eckart的连续拉格朗日方程，获得离散连续方程和加速度方程。使用连续表面力模型来满足以下事实：表面力可能无法在界面的每一侧均匀分布。对于具有大密度比的界面流动，对壁的自由滑移和不滑移条件施加了改进的边界条件。通过在界面附近施加法线校正（称为Interface-PSA），为界面流动添加了粒子移动算法（PSA）。然后是四个有代表性的数值示例，包括液滴变形，瑞利泰勒不稳定性，提出了溃坝和气泡上升的情况，并与参考数据进行了比较。结果表明，可以很好地捕获固有的界面流物理学，包括表面张力和复杂界面的动态演化。