Author(s)

N. Evstigneev

Abstract

The incompressible system of Navier-Stokes equations for an Initial-Boundary Value Problem is solved on an unstructured tetrahedral grid using a finite volume method. Implementation of a free surface calculation is done by using a combination of Level Set and Volume Of Fluid methods. A numerical scheme utilizes the method of fractional steps based on the predictor-corrector method and the artificial compressibility method. Invariant features of a tetrahedron are used in order to calculate fluxes over a control volume with higher order. A high order approximation in Navier-Stokes and VOF level set advection equations is made by a TVD SuperBEE scheme. The turbulence model is based on LES methodology. In order to decrease the time of solution for a large geometry, a distributed computation routine is incorporated into the method. The distributed calculation is based on a TCP/IP network and can use personal computers under Windows or UNIX. The efficiency of the distributed calculation is shown. The method is verified by comparison of results with other calculations and experiments – cavity flow case, dam break free surface flow case, turbulent flow in a circular pipe case – Poiseuille flow (turbulent energy distribution). The method is successfully used for CFD simulation of water intake on Zagorskaya Hydraulic Power Plant (Russia). The results are close between laboratory experiments and CFD computations. Keywords: unstructured grid, finite volume method, artificial compressibility method, predictor-corrector method, Navier-Stokes equations, distributed computation.

Keywords

unstructured grid, finite volume method, artificial compressibility method, predictor-corrector method, Navier-Stokes equations, distributed computation.