## Preprint 2015-11

## Sebastiano Boscarino, Raimund Bürger, Pep Mulet, Giovanni Russo, Luis M. Villada:

### On linearly implicit IMEX Runge-Kutta methods for degenerate convection-diffusion problems modeling polydisperse sedimentation

### Abstract:

Implicit-explicit (IMEX) Runge-Kutta (RK) methods are suitable for the solution of nonlinear, possibly strongly degenerate, convection-diffusion problems, since the stability restrictions, coming from the explicitly treated convective part, are much less severe than those that would be deduced from an explicit treatment of the diffusive term. A particularly efficient variant of these schemes, so-called linearly explicit IMEX-RK schemes, arise from discretizing the diffusion terms in a way that more carefully distinguishes between stiff and nonstiff dependence, such that in each time step only a linear system needs to be solved. These schemes provide an efficient tool for the numerical exploration of sediment formation and composition under a strongly degenerate polydisperse sedimentation model.

This preprint gave rise to the following definitive publication(s):

**Sebastiano BOSCARINO, Raimund BüRGER, Pep MULET, Giovanni RUSSO, Luis M. VILLADA: ***On linearly implicit IMEX Runge-Kutta methods for degenerate convection-diffusion problems modeling polydisperse sedimentation*. Bulletin of the Brazilian Mathematical Society, (New Series), vol. 47, 1, pp. 171-185, (2016).