EVALUATION OF AN UNFACTORED METHOD FOR THE SOLUTION OF THE INCOMPRESSIBLE-FLOW EQUATIONS USING ARTIFICIAL COMPRESSIBILITY

This paper presents a numerical scheme to solve the incompressible flo w equations with the target application being the prediction of hydrod ynamic loads acting on marine structures. The scheme is based on the c oncept of artificial compressibility and makes use of higher order imp licit upwind discretisation on multiblock structured meshes and an unf actored implicit time discretisation to solve for unsteady flows. The linear system arising at each implicit time step is solved using a pre conditioned conjugate gradient type method. Approximate Jacobian matri ces were used to reduce the memory requirements and improve the speed of computation. The main conclusion is that the numerical method is fo und to work well for a range of steady and unsteady flows with little sensitivity to the artificial compressibility parameter beta. (C) 1998 Elsevier Science Ltd. All rights reserved.