A Comparative Numerical Study of Solitary Wave Interaction with Concave, Convex, and Sloped Seawalls: Hydrodynamics, Wave Loads, and Turbulent Flow Analysis

Abstract Seawalls are critical for coastal protection, yet a comprehensive understanding of how their geometry affects hydrodynamic loads, performance, and local turbulence remains incomplete. While previous studies have investigated solitary wave forces on conventional vertical or sloped structures, a systematic comparative analysis of concave, convex, and sloped seawalls one that holistically links hydrodynamic performance (run-up, reflection), wave-induced loads, and the resulting turbulent flow structures has been a notable gap in the literature. This study addresses this gap by conducting a detailed numerical investigation using a validated RANS model coupled with a k-ε RNG turbulence scheme and the Volume of Fluid (VOF) method. We analyze the interaction of highly nonlinear solitary waves with these distinct geometries. The results demonstrate that seawall curvature is a critical design parameter. Concave seawalls significantly increase wave reflection and generate concentrated, high-energy vortices at the structure's toe, leading to amplified wave loads and a higher potential for local scour. In contrast, convex profiles promote smoother flow separation, resulting in reduced wave forces and diminished turbulence near the bed. Sloped seawalls are effective at dissipating energy along the structure's face, thereby minimizing loads but increasing the likelihood of significant overtopping. By providing an integrated analysis of pressure distribution, impact forces, and Turbulent Kinetic Energy (TKE), this research offers crucial insights for the optimal design of coastal defenses, enabling engineers to balance structural stability, hydrodynamic efficiency, and scour mitigation.