气液两相流界面多尺度问题可计算性研究进展

Progress of computability of multi-scale interface problems in gas-liquid two-phase flow

气液两相流复杂多变的界面结构在瞬态时间上具有宽广的空间尺度范围。界面多尺度问题涉及化工领域、核安全领域以及其他多个领域,其可计算性是当前国内外气液两相流领域的研究焦点之一。分析了欧拉体系下处理气液两相流相界面不连续性的两种基本模型以及湍流模拟方法对界面结构的影响。针对离散流界面尺度分布性和混合流界面跨尺度性两类多尺度问题,分析了可计算性研究面临的困境,将其归因于网格尺度的约束、几何及物理边界的缺失。重点归纳了混合流界面跨尺度性问题的计算方法以及典型应用。最后对气液两相流界面多尺度问题提出了应对策略及研究趋势,为此类问题研究提供有益的参考。

Gas-liquid two-phase flow has complex interface structures with a wide range of spatial scales in the transient time. The multi-scale interface problems are related to various fields, such as chemical engineering, nuclear safety, and so on. Computability of these problems is one of the research priorities. This paper analyzes basic models dealing with the discontinuity of phase interfaces in the Eulerian reference frame, and describes the influence relationship between turbulent simulation methods and interfaces. The difficulties of computability are analyzed for two types of multi-scale problems： scale distribution of interfaces in dispersed flows and cross-scale of interfaces in mixed flow. Two factors including the scale for computational grid and the loss of geometry and physical boundaries are concluded. The computing methods and typical applications in cross-scale of interfaces in mixed flow are summarized. The strategies and trends of the research on those multi-scale problems are proposed, providing useful guides for the research.