Prediction of Compressible Viscos Flows at Low Mach Number

Results of prediction of the unsteady compressible Navier-Stokes equations at low Mach number, that demonstrate facilities of the new method are presented. Viscous gas flows in enclosed domains and in channels were predicted, namely: (a) a laminar free convective air flow in a square cavity with a differently heated walls and (b) laminar mixed convective air flows through a channel with strong local heating. It is shown that efficiency of the new method does not depend on Mach number when it tends to zero. The problems have been solved on the sequence of space and time grids in order to examine accuracy of the new method. It is shown that the method provides second-order accuracy in space and first-order accuracy in time. A comparative study of the new method and three variants of the standard SIMPLE-like approaches was conducted in order to investigate accuracy and robustness of the mrt hods. The Boussinesq approximation and the full Navier-Stokes equations were compared too.