Yu HU, Xiaohua HUANG, Haiyang LIU, Qiyou TAO, Shaomin WANG, Taiping YUAN

Numerical Analysis of the Dynamic Response of a Single-Point Mooring Fish Cage in Waves and Currents

In this study, we developed a numerical model of a single-point mooring (SPM) cagesystem based on the finite element method, and employed it to simulate the dynamicresponse of the cage system under conditions with waves and currents. We focusedmainly on the mooring line tension and deformation for the cage collar. The simulatedresults indicated that adding a buoy as part of a cage system was helpful for reducingthe force and deformation of the cage collar, and the current contributed greatly tothe total load on the cage system. In addition, the location of the greatest deformationof the cage collar was confirmed by comparing the stress results for different points inthe collar structure when exposed to strong waves and current. Therefore, to avoidplastic failure, we tested a connected component with a lower pipe diameter to wallthickness ratio to effectively reduce the deformation of the floating pipes, therebyenhancing the security of the SPM cage system under severe sea conditions.Furthermore, we analyzed and discussed the effects of the material characteristics onthe dynamic properties of the SPM cage system.

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