Rotating stall is a common instability phenomenon that occurs in turbomachinery. Rotating stall 3D instability can be characterized as one or more stall cells rotating at a fraction of rotor velocity. In this article, the ANSYS Fluent software was used to numerically simulate entropy generation. The relative velocity of the monitoring points in the rotor is discussed, and the type of stall inception is a spike. In addition, five typical conditions that affect the evolution of rotating stalls are presented and discussed with respect to characterizing entropy generation in a two-stage variable-pitch axial fan. The results reveal that entropy generation significantly improves after the stall phenomenon appears. Because rotating stall first occurs in the second rotor, its entropy production is higher than that of the first rotor over the entire evolution period. The high entropy generation region moves in the circumferential and radial directions of the first and second rotors during the evolution of rotating stall.

中文翻译：

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两级变螺距轴流风机旋转失速演化过程中熵产生的模拟

旋转失速是涡轮机械中常见的不稳定性现象。旋转失速3D不稳定性的特征在于一个或多个失速单元以一部分转子速度旋转。在本文中，ANSYS Fluent软件用于数值模拟熵生成。讨论了转子中监测点的相对速度，失速开始的类型是峰值。此外，针对表征两级变螺距轴流风机中的熵产生，提出并讨论了影响旋转失速演变的五个典型条件。结果表明，失速现象出现后，熵产生显着改善。因为旋转失速首先发生在第二个转子中，在整个演化过程中，它的熵产高于第一个转子。在旋转失速的发展过程中，高熵产生区域在第一转子和第二转子的周向和径向上移动。