A FINITE-VOLUME METHOD FOR FLUID-FLOW IN POLAR CYLINDRICAL GRIDS

In the numerical simulation of fluid flows using a polar cylindrical g rid, grid lines meet at a single point on the axis of the polar cylind rical grid system; this makes the grids around the axis degenerate fro m being general quadrilaterals into triangles. Therefore, a special tr eatment must be performed when the axis has to be included in the comp utational domain in order to solve a non-axisymmetrical fluid flow pro blem. In this paper a new numerical method has been developed to deal with the difficulty of the axis when the control volume technique is u sed with a non-staggered grid arrangement. Two illustrative examples o f the proposed method are presented for simulating the fluid flows on the axis and all the numerical results obtained for the two examples a re shown to be in good agreement with the available analytical solutio ns. (C) 1998 John Wiley & Sons, Ltd.