Marine fishery is gradually developing from the coastal area to the deep sea. The semi-submersible offshore fish farm is one of the most foreseeable aquaculture equipment. However, the vast and abundant deep sea also means that the fish farm will be in a harsh marine environment. A model test of a semi-submersible fish farm was carried out in this paper. In order to obtain the hydrodynamic response characteristics of the fish farm, the accelerations on five different positions and mooring forces of the model under different wave conditions and current were measured, the steady-state amplitudes of the first five harmonics experimental acceleration and mooring tension were obtained. The steady-state amplitudes of non-dimensional first-harmonic acceleration at different positions with different wave periods were compared, and the amplitude trends were analyzed. The influence of higher harmonics acceleration on the first ones was investigated. Besides, the amplitude trend of different harmonics acceleration was analyzed under different conditions. Furthermore, the trend and fluctuation range of mooring tension at front and aft positions under different conditions were compared, and the causes of occurrence of the peak value of the instantaneous amplitude were figured out.
New types of aquaculture equipment are gradually put into the ocean to relieve the environmental pressure in coastal area. As a typical new type of aquaculture equipment, semi-submersible fish farm is in a harsher marine environment than the traditional offshore cage. In order to ensure the normal operation of semi-submersible fish farm and the normal survival of aquaculture products, the hydrodynamic performance of which will be the focus of attention. The hydrodynamic analysis of semisubmersible fish farm is similar to that of traditional cage, but there are also differences.
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