A new family of linearly implicit fractional step methods is proposed for the efficient numerical solution of a class of nonlinear time-dependent reaction-diffusion equations. By using the method of lines, the original problem is first discretized in space via a mimetic finite difference technique. The resulting differential system of stiff nonlinear equations is locally decomposed by suitable ...

2;3 2;6 2;9 2;ll 3;l 3;3 3;5 13 (6) 13 (7) 26 (8) 38 ( 1 1 ) 63 (15) 5 1 112) 8 (6) 1 (1) 2 (1) 2 (1) 2 (1) 1 (1) 10 0) 2 (2) 6 (2) 1 (1) 4 (1) 7(l) 43 (8) 7 (5) 3 (1) 9 (6) 14 (8) 17 (6) 15 (4) 1 (1) 1 (1) 2 (2) l(1) 1 (1) 1 (1) 2 (1) TOTAL (

In this paper, we discuss convergence of the extrapolated iterative methods for solving singular linear systems. A general principle of extrapolation is presented. The semiconvergence of an extrapolated method induced by a regular splitting and a nonnegative splitting is proved whenever the coe cient matrix A is a singular M -matrix with ‘property c’ and an irreducible singular M -matrix, respe...

In this work, we present a cell-centered time-splitting technique for solving evolutionary diffusion equations on triangular grids. To this end, we consider three variables (namely the pressure, the flux and a weighted gradient) and construct a so-called expanded mixed finite element method. This method introduces a suitable quadrature rule which permits to eliminate both fluxes and gradients, ...

for solving large sparse non-hermitian positive definite linear equations, bai et al. proposed the hermitian and skew-hermitian splitting methods (hss). they recently generalized this technique to the normal and skew-hermitian splitting methods (nss). in this paper, we present an accelerated normal and skew-hermitian splitting methods (anss) which involve two parameters for the nss iteration. w...

We describe a highly flexible framework to solve 3D radiation transfer problems in scattering dominated environments based on a long characteristics piecewise parabolic formal solution and an operator splitting method. We find that the linear systems are efficiently solved with iterative solvers such as Gauss-Seidel and Jordan techniques. We use a sphere-in-a-box test model to compare the 3D re...