We present a novel divergence free mixture model for multiphase flows and the related fluid‐solid coupling. The new mixture model is built upon a volume‐weighted mixture velocity so that the divergence free condition is satisfied for miscible and immiscible multiphase fluids. The proposed mixture velocity can be solved efficiently by adapted single phase incompressible solvers, allowing for larger time steps and smaller volume deviations. Besides, the drift velocity formulation is corrected to ensure mass conservation during the simulation. The new approach increases the accuracy of multiphase fluid simulation by several orders. The capability of the new divergence‐free mixture model is demonstrated by simulating different multiphase flow phenomena including mixing and unmixing of multiple fluids, fluid‐solid coupling involving deformable solids and granular materials.

中文翻译：

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多相流体的无发散混合模型

我们提出了一种用于多相流和相关流固耦合的新型无散度混合模型。新的混合模型建立在体积加权混合速度的基础上，因此混相和不混相多相流体都满足无发散条件。建议的混合速度可以通过适应的单相不可压缩求解器有效求解，允许更大的时间步长和更小的体积偏差。此外，修正漂移速度公式以确保模拟过程中的质量守恒。新方法将多相流体模拟的精度提高了几个数量级。通过模拟不同的多相流动现象，包括多种流体的混合和不混合，证明了新的无发散混合模型的能力，