Design and force calculation of a new type of composite anti-wind and wave aquaculture net cage in marine environment

Different from traditional offshore cages, fences and other farming methods, deep-sea wind and wave resistant cages are suitable for the development of high-economic value fish farming, having become an important way for coastal fisheries to change production. In order to relieve the pressure of offshore aquaculture and expand deep-sea aquaculture, a new type of complex wind wave-resistant deep-sea aquaculture cage was designed based on the conditions of Chinese marine aquaculture. The cage gives up the traditional structure of floating frame and floating ring, and adopts the adjustable structure of double float to adapt to different sea conditions and reduce the phenomenon of middle arch and middle sag caused by rigid connection. In addition, the pendant body connected by the float and the three-dimensional floating frame can provide large pendant and longitudinal swing damping, and control the motion amplitude of the cage. At the same time, Morrison formula and Bernoulli equation were used to calculate the force of the cage under the environmental loads such as wind, wave and current, and the results were compared with the traditional high density polyethylene (HDPE) cage. The results show that the new compound wind-wave cage can withstand the environmental loads in the ocean better than the traditional HDPE cage, which provides a design reference for the subsequent research, and development of large-scale wind-wave cage culture.