Iterative Stokes Solvers in the Harmonic Velte Subspace.

We explore the prospects of utilizing the decomposition of the function space (H[sup 1, sub 0])[sup n] (where n = 2, 3) into three orthogonal subspaces (as introduced by Velte) for the iterative solution of the Stokes problem. It is shown that Uzawa and Arrow-Hurwitz iterations — after at most two initial — steps can proceed fully in the third, smallest subspace. For both methods, we also compute optimal iteration parameters. Here, for two-dimensional problems, the lower estimate of the inf-sup constant by Horgan and Payne proves useful and provides an inclusion of the spectrum of the Schur complement operator of the Stokes problem. [ABSTRACT FROM AUTHOR]