Abstract In various industrial combustion devices, such as liquid rocket engines at ignition or Diesel engines during the compression stage, the operating point varies over a wide range of pressures. These pressure variations can lead to a change of thermodynamic regime when the critical pressure is exceeded, switching from two-phase injection to transcritical injection. Such change modifies the topology of the flow and the mixing, thereby impacting the flame dynamics. This motivates the development of a unified methodology able to address both subcritical and supercritical flows within the same solver. To achieve this, the present work provides an extension of the supercritical real gas Taylor-Galerkin solver AVBP-RG to subcritical two-phase flows, based on diffuse interface models. In particular, the required developments for the integration of a multifluid model into the finite-element framework of this solver are detailed. Then, the ability of the solver to address a subcritical configuration is tested by simulating two subcritical-pressure operating points (G1 at 4.7 MPa and A10 at 1 MPa) of the MASCOTTE test bench operated by ONERA. This allows to confront the model with experimental data, showing good agreement.

中文翻译：

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用于模拟从亚临界状态到超临界状态的可压缩多组分分离两相流的多流体 Taylor-Galerkin 方法

摘要 在各种工业燃烧装置中，如点火的液体火箭发动机或压缩阶段的柴油发动机，其工作点在很宽的压力范围内变化。当超过临界压力时，这些压力变化会导致热力学状态发生变化，从两相注入切换到跨临界注入。这种变化会改变流动和混合的拓扑结构，从而影响火焰动力学。这促使开发能够在同一求解器内同时解决亚临界和超临界流的统一方法。为了实现这一点，目前的工作基于扩散界面模型，将超临界真实气体 Taylor-Galerkin 求解器 AVBP-RG 扩展到亚临界两相流。特别是，详细介绍了将多流体模型集成到该求解器的有限元框架中所需的发展。然后，通过模拟由 ONERA 操作的 MASCOTTE 测试台的两个亚临界压力操作点（G1 在 4.7 MPa 和 A10 在 1 MPa）来测试求解器解决亚临界配置的能力。这允许用实验数据面对模型，显示出良好的一致性。