English

Decoupling multistep schemes for elliptic-parabolic problems

Numerical Analysis 2025-07-14 v2 Numerical Analysis

Abstract

We study the construction and convergence of decoupling multistep schemes of higher order using the backward differentiation formulae for an elliptic-parabolic problem, which includes multiple-network poroelasticity as a special case. These schemes were first introduced in [Altmann, Maier, Unger, BIT Numer. Math., 64:20, 2024], where a convergence proof for the second-order case is presented. Here, we present a slightly modified version of these schemes using a different construction of related time delay systems. We present a novel convergence proof relying on concepts from G-stability applicable for any order and providing a sharper characterization of the required weak coupling condition. The key tool for the convergence analysis is the construction of a weighted norm enabling a telescoping argument for the sum of the errors.

Keywords

Cite

@article{arxiv.2407.18594,
  title  = {Decoupling multistep schemes for elliptic-parabolic problems},
  author = {Robert Altmann and Abdullah Mujahid and Benjamin Unger},
  journal= {arXiv preprint arXiv:2407.18594},
  year   = {2025}
}
R2 v1 2026-06-28T17:54:22.587Z