Multiscale modelling couples patches of nonlinear wave-like simulations

TL;DR

This paper extends the multiscale gap-tooth scheme to nonlinear wave-like systems, enabling efficient large-scale simulations by coupling small patches of microscale wave dynamics, demonstrated through dam-breaking wave simulations.

Contribution

It develops a high-order consistent multiscale scheme for wave systems, previously limited to dissipative systems, and demonstrates its effectiveness with practical dam-breaking wave simulations.

Findings

Feasible large-scale wave simulations with computational savings

High-order consistency achieved through classic macroscale interpolation

Successful application to dam-breaking wave scenarios

Abstract

The multiscale gap-tooth scheme is built from given microscale simulations of complicated physical processes to empower macroscale simulations. By coupling small patches of simulations over unsimulated physical gaps, large savings in computational time are possible. So far the gap-tooth scheme has been developed for dissipative systems, but wave systems are also of great interest. This article develops the gap-tooth scheme to the case of nonlinear microscale simulations of wave-like systems. Classic macroscale interpolation provides a generic coupling between patches that achieves arbitrarily high order consistency between the multiscale scheme and the underlying microscale dynamics. Eigen-analysis indicates that the resultant gap-tooth scheme empowers feasible computation of large scale simulations of wave-like dynamics with complicated underlying physics. As an pilot study, we implement numerical simulations of dam-breaking waves by the gap-tooth scheme. Comparison between a gap-tooth simulation, a microscale simulation over the whole domain, and some published experimental data on dam breaking, demonstrates that the gap-tooth scheme feasibly computes large scale wave-like dynamics with computational savings.