圆柱绕流低维Galerkin方法的推广

把求解静止圆柱绕流问题的低维Ｇａｌｅｒｋｉｎ方法推广至可以求解绕横向或流向振动圆柱、旋转或旋转振荡圆柱等多种流动问题．方法的关键在于对以上四种流动分别选取不同的基本模态，使之满足相应的边界条件．对于振动或旋转振动圆柱绕流问题，它们与时间有关．于是扰动模态满足齐次边界条件，可以由此构造标准的Ｇａｌｅｒｋｉｎ算法．算例表明，用推广了的低维Ｇａｌｅｒｋｉｎ方法定性研究上述流动问题简便实用．

Generalizations of the Low Dimensional Galerkin Method for Flows Round a Circular Cylinder

In this paper the low dimensional Galerkin method for flows round a stationary circular cylinder is generalized to flows round a cross or in line oscillating circular cylinder, a rotating or rotationary oscillating circular cylinder, etc. The key point of the method is the choice of a proper basic mode for each of the above flows satisfying the corresponding boundary conditions. For the case of flows past an oscillating or rotationary oscillating circular cylinder, the basic mode is time dependent. Then pertubation modes satisfy all homogeneous boundary conditions and can be used to apply the standard Galerkin method. Examples show that the present generalized methods are simple and applicable to studies on the flows mentioned above qulitatively.