Viscous Flow Fields Induced by the Run-Up of Periodic Waves on Vertical and Sloping Seawalls

Abstract

Unsteady two-dimensional Reynolds Averaged Navier-Stokes (RANS) equations coupled with the k−ε turbulence model was developed to simulate the viscous flow field near seawalls. The complex free-surface configuration was captured using the particle level set method (PLSM). An innovative solid-fluid coupling method was employed to mimic the solid-fluid interaction on fixed Cartesian grids. The proposed numerical model was applied to investigate the viscous flow fields induced by periodic waves propagating on three different seawalls, including vertical and steep seawalls, which are commonly designed in Taiwan with slopes of 1:2 and 1:5. The results reveal that the wave run-up height is closely related to Iribarren number and breaking wave. Partial standing wave or asymmetric recirculating cells in front of a steep seawall lose symmetry with increasing slope. The wave pressure on the seawall face increases as the Ursell number or seawall slope increases. The undertow caused by breaking waves has a significant effect on the bottom shear stress in front of the seawall.

Energy Transfer and Reverse Flow Characteristics in the Interaction Process between Non-Breaking Solitary Wave and a Steep Seawall: A Case Study

“…A numerical wave tank developed in previous studies [41,42] was applied in this research. The continuity equation, unsteady Reynolds-averaged Navier-Stokes (RANS) equations, and low-Reynolds-number κ − ε turbulent model were discretized and solved using finite analytic methods [43] under two-dimensional Cartesian coordinates.…”

“…Ref. [42] utilized the same numerical model to simulate the impact of periodic waves on typical seawalls in Taiwan, which included vertical seawalls and steep seawalls with slope ratios of 1:2 and 1:5. The study also investigated the occurrence of partial standing waves or asymmetric recirculating cells, as well as the wave pressures on the seawall surface and the undertow resulting from breaking waves at different seawall slopes.…”

“…In the early stages of this study, we applied a self-developed numerical model to simulate the run-up and run-down processes of periodic waves in front of common seawalls along the west coast of Taiwan [42]. To investigate the impact of waves on these seawalls, we set the wave conditions in the model for a non-breaking solitary wave and focused on seawalls with a typical slope of 1:3.…”