Numerical investigations of wave loads on fixed box in front of vertical wall with a narrow gap under wave actions

Abstract Violent fluid oscillations may appear inside the narrow gap between multiple structures in close proximity and cause severe damage to such structures and safe operations. Here, based on the OpenFOAM® package, this paper presents a numerical investigation of wave loads during gap resonance between a fixed box and a vertical wall by utilizing a two-dimensional (2D) numerical wave flume. The box-wall system is subjected to incident regular wavesco with various wave heights and frequencies. The topographies of plane slopes with various inclinations are arranged in front of the vertical wall. This paper focuses on the influences of the topographical variation on the wave loads, including the horizontal wave force, the vertical wave force and the moment on the box. It is found that all the frequencies, at which the maximum horizontal wave force, the maximum vertical wave force and the maximum moment appear, decrease with the increase of topographical slope, S, overall. Moreover, these frequencies are also shown to deviate from the fluid resonant frequency to different degrees. For all the incident wave heights considered, both the maximum horizontal wave force and the maximum moment present a pattern of fluctuation with the topographical slope.