We present an efficient and stable method for simulating the two-way coupling of incompressible fluids and deformable bodies. In our method, the fluid is represented by particles, and simulated using divergence-free incompressible smoothed-particle hydrodynamics (ISPH). The deformable bodies are represented by polygonal meshes, where the elastic deformations are simulated using a position-based dynamics scheme. Our technique enforces incompressibility on the fluid using divergence-free constraints on the velocity field, while it effectively simulates the physical features of deformable bodies. Most current ISPH methods are struggling with the issue of free-surface boundary conditions. We handle this problem by introducing a novel free-surface formulation, where our free-surface model obviates the need to identify the surface particles. For the interaction between the fluid and the deformable solids, we model the forces that both phases, fluid and solid, exert upon each other. We demonstrate that our approach effectively handles complex coupling scenarios between fluids and thin deformable shells or highly deformable solids, and produces plausible results.

中文翻译：

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ISPH-PBD：不可压缩流体和变形体的耦合模拟

我们提出了一种有效且稳定的方法来模拟不可压缩流体和可变形体的双向耦合。在我们的方法中，流体由粒子表示，并使用无发散不可压缩平滑粒子流体动力学 (ISPH) 进行模拟。可变形体由多边形网格表示，其中使用基于位置的动力学方案模拟弹性变形。我们的技术使用对速度场的无发散约束来增强流体的不可压缩性，同时它有效地模拟了可变形体的物理特征。大多数当前的 ISPH 方法都在努力解决自由表面边界条件的问题。我们通过引入一种新的自由表面公式来处理这个问题，其中我们的自由表面模型不需要识别表面粒子。对于流体和可变形固体之间的相互作用，我们对流体和固体这两个相相互施加的力进行建模。我们证明我们的方法有效地处理了流体与薄可变形壳或高度可变形固体之间的复杂耦合场景，并产生了合理的结果。