ACCURACY VERSUS COST FOR 3 EFFICIENT FINITE-ELEMENT SOLVERS

Three efficient finite-element schemes are compared for Poisson proble ms on triangular meshes: (1) uniform subdivision of first order triang les and the incomplete-Choleski conjugate gradient method; (2) uniform subdivision of first-order triangles and a multilevel-preconditioned conjugate gradient method; and (3) uniform increase of polynomial olde r and diagonally-preconditioned conjugate gradients, Errors in the com puted energy, and computational costs, are obtained for a square, air- filled coaxial cable; a linear, curl ent-driven magnetostatic problem; and a microstrip transmission line. Increasing the polynomial order i s by far the best approach, i.e. gives the best accuracy for a given c ost.