Experimental investigation of damping effect of porous structures on hydrodynamic response of a floating closed aquaculture tank in beam regular waves

Porous structures are extensively adopted in ocean engineering applications for their exceptional ability in dissipating waves. A multi-tank floating closed containment system (FCCS) was designed, and a series of experimental tests were conducted to analyze the damping effect of side-mounted porous structures on dynamic responses of the FCCS in beam regular waves, with two porous structures of the perforated baffle and porous layer considered. The effect of the porosity of the perforated baffle and filling level inside fish tanks was examined. Results reveal the proposed side-mounted porous structures exhibit satisfactory effects in anti-motion by turning the coupling effect between roll and heave motion. The baffle porosity of nb = 0.2 is the final suggested porosity due to the optimal anti-sloshing and anti-motion capability. Additionally, the porous layer can reduce the amplitude of the free water surface on the weather side of fish tanks effectively, particularly in rough sea conditions. Moreover, the performance of side-mounted porous structures can be optimized by increasing the filling depth, indicating the proposed porous structures are more applicable to the large filling depth required for FCCS aquaculture. Overall, the results of this study establish a valuable database for the future construction and material selection of the multi-tank FCCS.