Numerical simulation and PIV measurements of the wave-induced flow field near semi-circular breakwaters

Abstract

Abstract Careful design of the high-tech semi-circular breakwaters (SBW), which are used for protection against sea waves, is essential to avoid the failure of these large-scale projects. An improved design tool adopting numerical simulations, complemented with experimental measurements is introduced. Unstructured boundary-fitted grids are used to model the curved SBW boundary accurately and resolve the flow adjacent to it. Experimental measurements based on Particle Image Velocimetry (PIV) are introduced and the numerically simulated velocity fields are validated. For the first time, the strong free surface deformation upstream of the SBW, termed trough-breaking, is reproduced numerically. The phenomenon is investigated in detail and its impact on several SBW advantages and stability is emphasized. The improved accuracy due to unstructured boundary-fitted grids complemented by the PIV data set, offers valuable prospects for performing complex designs and exploring future applications. Article Highlights An efficient design tool for the high-tech semi-circular breakwater is introduced adopting numerical simulations and experimental measurements. The numerical results agree well with the experimental measurements. Hence, this experimental data set should be used extensively for validation in future studies. The important flow phenomenon of “trough-breaking” is reproduced numerically for the first time, and its impact on the semi-circular breakwater features is clarified.

Keywords

• Semi-circular breakwater
• PIV
• Unstructured grid
• Wave breaking