Hydroelastic analysis of oblique wave interaction with submerged L-shaped Jarlan-type breakwater

Abstract

This study explores the hydroelastic response of surface waves interacting with a submerged L-shaped Jarlan-type breakwater system, featuring a perforated front plate and a rigid rear plate attached above the left edges of two solid rectangular blocks to create an innovative L-shaped configuration. The entire breakwater system is submerged below a water surface that is covered by an infinite, continuous thin elastic plate of uniform thickness, governed by the Euler–Bernoulli beam theory. Distinctively, the present work accurately accounts for the submergence depth of the rectangular block within L-shaped configuration, along with the influence of the elastic plate’s thickness—factors often neglected in previous studies. This important consideration reveals new insights into wave–structure interactions under an elastic sheet, motivating the present analysis within the framework of linearized water wave theory. To analyze the wave interaction, the associated boundary value problem is reformulated into a system of integral equations. These equations are then solved approximately using a multi-term Galerkin method, which proves highly effective in handling the inherent singularities: specially, the square-root singularities at the submerged tips of the thin plates and the one-third singularities at the sharp corners of the solid rectangular blocks. A comprehensive numerical investigation is carried out to examine the influence of key physical parameters on the reflection and transmission coefficients, energy loss, horizontal wave forces acting on each plate and the surface displacement under various wave conditions. Graphical analyses further reveal that the present breakwater system offer a significant advantage over the traditional Jarlan-type configuration (as studied by Liu et al. (2014)). Both the perforated front plate and the rigid rear plate experience notably reduced horizontal wave forces compared to those in the conventional Jarlan-type model, highlighting the improved efficiency and structural stability of the proposed design.