SOLUTION OF NAVIER-STOKES EQUATIONS ON NON-STAGGERED GRID

When Navier-Stokes equations are solved on a non-staggered grid, the problem of checker board prediction of pressure is encountered. Over the last ten years, this problem has been cured by what is known as the momentum interpolation formula which is applied for evaluation of the cell-face velocities. In this paper two contributions are made. Firstly, it is shown that the momentum interpolation formula is a special case of a more general interpolation relationship that can be derived from a physical principle. In this sense, the relationship does not provide a unique formula for the interpolation of the cell-face velocity. In order to achieve unique interpolation practice, the second contribution of this paper relates to pressure-gradient interpolation. The results obtained from pressure-gradient interpolation compare extremely favourably with those obtained using staggered grid.