Consider the interaction of biharmonic waves with a periodic array of cavities, characterized by the Kirchhoff–Love model. This paper investigates the perfectly matched layer (PML) formulation and its numerical solution to the governing biharmonic wave equation. The study establishes the wellposedness of the associated variational problem employing the Fredholm alternative theorem. Based on the examination of an auxiliary problem in the PML layer, exponential convergence of the PML solution is attained. Moreover, it develops and compares three decomposition methods alongside their corresponding mixed finite element formulations, incorporating interior penalty techniques for solving the PML problem. Numerical experiments validate the effectiveness of the proposed methods in absorbing outgoing waves within the PML layers and suppressing oscillations in the bending moment of biharmonic waves near the cavity’s surface.

Publication:

IMA Journal of Numerical Analysis (2025) 00, 1–45

https://doi.org/10.1093/imanum/draf025

Author:

PEIJUN

LI LSEC, ICMSEC, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190, China

XIAOKAI YUAN

School of Mathematics, Jilin University, Changchun 130012, China

Corresponding author

yuanxk@jlu.edu.cn