A domain decomposition method for simulating advection dominated, externalincompressible viscous flows

We introduce a domain decomposition method for simulating 2D external, inco mpressible viscous flows, In each subdomain that is close to a connected ph ysical boundary, the velocity and the pressure are approximated on a body f itted, finite difference grid. In the subdomain that is far from the solid boundary (i.e,, the neighborhood of infinity), we develop a characteristics method to approximate the velocity and the vorticity on a Cartesian grid. The two methods are coupled by means of a Schwarz type strategy. This metho d is tested by simulating the flow past one or two cylinders. Some tests ar e performed with moving cylinders. Comparisons with numerical and experimen tal data illustrate the efficiency of the method. (C) 2000 Elsevier Science Ltd. All rights reserved.