Experimental study on hydrodynamic performance of the semi-submersible vessel-shaped fish cage

Deep-sea net cages play a vital role in expanding offshore farming in modern marine fisheries. In this paper, a model-scale 1:40 tank experiment was conducted for a vessel-shaped truss-structured single-point mooring deep-sea aquaculture net cage. The study focused on the hydrodynamic characteristics, including the effect of current, wave, and net on the mooring force, heave, and pitch motion behaviors. Experimental results indicate that the mooring force increases with the current velocity, draught of the cage, and wave height, but decreases with the wave period increase. Both heave and pitch movements amplitudes increase with wave height. While heave motion amplitude initially declines and then ascends with wave periods, pitch motion shows the opposite pattern. Besides the net has an obvious damping effect on the pitch motion. These results can provide data support for the design and offshore installation of vessel-shaped truss-structured net cages in the future.