Viscous Splitting Algorithm Applied to Low Reynolds Number Flow Round a Circular Cylinder

摘要

The established method of splitting the equations of flow into separate convection and diffusion equations, the solutions of which are superposed to provide an approximate solution, is presented with a new vorticity diffusion treatment. Test cases which show the accuracy of the method in several simple flows are presented. The method is applied to low Reynolds number flows about circular cylinders with steady and oscillating wakes. The diffusion method involves a direct exact solution for the diffusion of vorticity at each time step followed by rediscretization onto a mesh of grid points. Comparison with a finite element solution and with experimental results shows good agreement up to a Reynolds number of 200, the extent of the range studied.