A Time-integration Method Using Artificial Compressibility For Unsteady Viscous Flows

Abstract A time-accurate integration method for the study of unsteady incompressible viscous flows is presented, based on a three-point-backward implicit discretization of the Navier-Stokes equations in real time and a pseudo-time relaxation with artificial compressibility to advance the solution between consecutive real time levels. The spatial discretization uses central differencing based on a stretched staggered grid. A factored ADI scheme with lagged non-linearities is used to reduce the problem to the solution of scalar tridiagonal systems. This method displays very good computing efficiency and accuracy when applied for validation to several typical steady and unsteady flow problems.