1994 Volume 60 Issue 579 Pages 3797-3804
In general, three-dimensional flow structures are observed in the Karman vortex street behind a circular cylinder when Reynolds number ≥ 200, and it is pointed out that three-dimensional analysis is necessary to simulate such flow structures. In this study, incompressible flow past a stationary circular cylinder at Reynolds number 1100 is computed by finite difference method, and the three dimensional computation shows good agreement with experimental values. Furthermore, a phenomenon that periodic lift and drag forces acting on a cylinder cause a beat frequency can be simulated. This phenomenon cannot be observed in the two-dimensional calculation, and the mechanism is explained on the basis of the relationship between the fluctuating fluid forces and the flow structures in the three-dimensional calculation.