A vorticity-based method for incompressible unsteady viscous flows

A novel approach is presented, based on the integral form of the vorticity formulation, in which the vorticity transport equation is solved by using t he cell-centred finite-volume method, while the velocities needed at the ce ntre of each control volume are calculated by a modified Biot-Savart formul a in conjunction with a fast summation algorithm. The vorticity and mass co nservation in the flow are guaranteed during the calculation by virtue of t he finite volume approach and the method of implementing the boundary condi tions at the body surface. As an example, both the early stage development and long term evolution of the flow around an impulsively started circular cylinder are computed using the method. The present results are compared wi th other numerical and experimental results for the same flow problem and s how good agreement. (C) 2001 Academic Press.