An efficient segregated algorithm for incompressible fluid flow and heat transfer problems-IDEAL

Recently an efficient segregated solution procedure for incompressible fluid flow and heat transfer problems, called IDEAL (Inner Doubly-iterative Efficient Algorithm for Linked-equations), has been proposed by author. In the algorithm there exist inner doubly-iterative processes for pressure equation at each iteration level, which almost completely overcome two approximations in SIMPLE algorithm. Thus the coupling between velocity and pressure is fully guaranteed, greatly enhancing the convergence rate and stability of solution process. In the present paper the property of the IDEAL algorithm for three-dimensional incompressible fluid flow and heat transfer problems is analyzed by the comparison between the algorithm and three most widely-used algorithms (SIMPLER, SIMPLEC and PISO). By the comparison for two application examples we can find that the IDEAL algorithm, which can converge almost at any under-relaxation factor, is far more robust than SIMPLER, SIMPLEC and PISO algorithms. When each method uses its own optimal under-relaxation factor, the IDEAL algorithm can reduce the computation time by 12.9%-52.6% over SIMPLER algorithm, by 48.3%-79.1% over SIMPLEC algorithm and by 10.7%-46.5% over PISO algorithm.