Targeted attenuation of spurious reflections in coupled wave propagation simulations

Journal article

Unphysical wave reflections pollute a domain’s solution when high frequency waves propagate from a fine to a coarse spatial discretisation. Inspired by the selective perfect matching layer, we look to specifically target and dampen the incompatible frequencies that cause the energy entrapment of spurious waves. In this work, we propose a Shepard-based projection method that filters with the inverse-distance weighting kernel—an alternative and simple to implement basis. We demonstrate the method in dynamically coupled finite element subdomains, that vary not only in mesh size, but also respective time steps. The attenuation is applied to a two-subdomain coupling, where explicit computations are leveraged to obtain a coarse-field representation of an interface. Performance of the proposed filter demonstrates a 99% attenuation of spurious reflections across a wide range of incompatible frequencies. Furthermore, through combining the Shepard-based projection with multi-time step integration and non-matching meshes, significant speedups in runtime can be achieved.

Authors: Chan, KF; Bombace, N; Falco, S; Chapman, D; Petrinic, N

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Computational Mechanics
• Pages: 1-31
• Publication date: 2026-07-29
• DOI: 10.1007/s00466-026-02826-2
• EISSN: 1432-0924
• ISSN: 0178-7675
• Language: English
• Keywords: Computation; Simple (philosophy); Weighting; Projection (relational algebra); Finite element method; Filter (signal processing); Spurious relationship; Attenuation