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一、引言叶栅绕流问题是水轮机设计和分析中的一个基本问题。叶栅绕流计算能为设计的优化提供有用的信息,它是减少模型试验、扩大选型范围、预测流场各种效应的有效手段。叶栅绕流计算的方法很多,早期应用保角变换法、奇点分布法等进行计算;随着计算机和数值法的发展,差分法和有限元法已被普遍应用。差分法较简便,并能灵活选择具有各种性能的格式,但对不规则边界的处理较困难。有限元法能处理不规则边界,但计算较复杂,计算耗费机时也较多。
I. Introduction The flow around the cascade is a basic problem in turbine design and analysis. Calculation of flow around cascades can provide useful information for design optimization. It is an effective way to reduce model test, expand selection range and predict various effects of flow field. There are many methods to calculate the flow around cascades, and the methods of conformal transformation and singular point distribution are used in the early stage. With the development of computer and numerical method, difference method and finite element method have been widely used. The difference method is simpler and has the flexibility to choose a format that has various properties, but the handling of irregular boundaries is more difficult. Finite element method can deal with irregular boundaries, but the calculation is more complex, more time-consuming calculation.