An a priori grid permutation for isothermal flow models

Abstract Mesh permutations are used to enhance the computational efficiency of an implicit finite element based scheme for modeling isothermal incompressible viscous flow through a permeable medium. A new software implementation of the implicit algorithm permits a realization of these potential savings and is discussed in some detail. The efficiency of the modeling application is shown to be particularly sensitive to the ordering of the grid nodes. An a priori arrangement of nodes approximating the order of their activation (fill) during the actual simulation is indicated. A new ordering procedure is proposed to achieve this task. The algorithm utilizes both geometric relationships and modeling parameters and demonstrates predictive capabilities analogous to the actual flow simulation while requiring a fraction of the computational resources. Examples are used to verify and quantify the efficiency projections and to investigate the apparent contradictory objectives of the proposed grid permutation with those of the more familiar profile or bandwith minimization procedures.