Study of the propagation of sound in a single non-ideal fluid originates with Stokes in 1845 and Kirchhoff in 1868. The situation is much more complex in the case of two-fluid flow, both from the physical point of view, as the configuration of the flow matters greatly, and from the analytical point of view. The principle two-fluid models currently in use for CFD are the focus of this article. It is shown that analytical expressions for the speed of sound depend heavily on the chosen model. These sound speed expressions are compared with experimental values. The consequences for CFD models are discussed in the final section of this paper. We outline the fact that any physical model, (on which numerical models could be based through numerical methods) should propagate the pressure-waves in a physically meaningful manner coherent with experimentation. Hence we question the relevance of physical models that imply two sound speeds (e.g.one per fluid). Whatever is the numerical scheme, it is not reasonable to assume that it could correct the physical model.

对单一非理想流体中声音传播的研究起源于 1845 年的 Stokes 和 1868 年的 Kirchhoff。在双流体流动的情况下，情况要复杂得多，无论是从物理角度来看，因为从分析的角度来看，流程非常重要。目前用于 CFD 的原理二流体模型是本文的重点。结果表明，声速的解析表达式在很大程度上取决于所选模型。将这些声速表达式与实验值进行比较。CFD 模型的后果将在本文的最后一节讨论。我们概述了一个事实，即任何物理模型（数值模型可以通过数值方法建立在其基础上）应该以与实验相一致的物理上有意义的方式传播压力波。因此，我们质疑暗示两种声速（每个流体各自不同）的物理模型的相关性。无论数值方案是什么，假设它可以校正物理模型是不合理的。