Hydrodynamic performance of TPMS structures as bioinspired submerged breakwaters for incident wave energy attenuation

This work numerically examines the hydrodynamic performance of triply periodic minimal surface (TPMS) structures used as bioinspired submerged breakwaters for solitary wave attenuation. Four TPMS geometries (Gyroid, Schwarz P, Schwarz D and Lidinoid) with identical porosity of 0.5 are modeled in a three-dimensional numerical wave tank using the open-source CFD solver REEF3D:CFD. The model is validated against published solitary-wave experiments involving submerged slotted barriers. Wave gauges with two-gauge decomposition are employed to determine reflection, transmission and dissipation coefficients together with wave-induced horizontal forces. Results show that all TPMS breakwaters significantly reduce transmitted wave heights. At the same time, the Gyroid topology provides the most balanced performance, combining the lowest reflection coefficient, the highest dissipation coefficient and the largest reduction in transmitted energy. Compared with the conventional solid breakwater, the Gyroid-based design decreases the peak horizontal wave force by more than 30% while achieving a slightly lower transmission coefficient. It has the best capacity to convert incident wave energy into internal turbulence and wake vortices.