Abstract In this work, a mixing cell closure model was derived in a Lagrangian formulation based on the hypothesis of isentropic compression or expansion. The proposed closure model is used to construct a five-equation model for the simulation of multifluid and multiphase flows. Thereafter a global ALE(Arbitrary Lagrangian-Eulerian) method was developed for the five-equation model. The five-equation based ALE method is a two-stage ALE method, including a Lagrangian phase and a rezone-remap phase. In the first phase, the model equation was discretized with a cell-centered Lagrangian scheme, and a multifluid Riemann solver was proposed by extending traditional Riemann solver to mixed cells with different materials. The five-equation based ALE method can be used to simulate multi-material flows with large deformation, which is a challenge for many traditional ALE methods. Moreover, it can be used to simulate multiphase flows. A series of multi-material and multiphase test problems were simulated with the five-equation based ALE method, and numerical results agree well with exact solutions and reference results.

中文翻译：

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一种基于五方程模型的可压缩多流体多相流全局ALE方法

摘要 在这项工作中，基于等熵压缩或膨胀假设，在拉格朗日公式中导出了混合单元闭合模型。所提出的闭合模型用于构建用于多流体和多相流模拟的五方程模型。此后，为五方程模型开发了全局 ALE（任意拉格朗日-欧拉）方法。基于五方程的 ALE 方法是一个两阶段的 ALE 方法，包括拉格朗日阶段和重区重映射阶段。在第一阶段，模型方程采用以单元为中心的拉格朗日格式进行离散化，并通过将传统的黎曼求解器扩展到不同材料的混合单元，提出了多流体黎曼求解器。基于五方程的ALE方法可用于模拟大变形的多材料流动，这对许多传统的 ALE 方法来说是一个挑战。此外，它还可用于模拟多相流。用基于五方程的ALE方法模拟了一系列多材料多相试验问题，数值结果与精确解和参考结果吻合较好。