Hydroynamic Performance And Optimization Analysis On The Mooring System For Deep-sea Aquaculture Vessel With Truss Structure

Since inshore aquaculture faces many problems such as environmental pollution,deepsea aquaculture has become an important development direction for aquaculture.The hydrodynamic characteristics and mooring mode have a significant impact on the safety and stability of aquaculture facilities.Therefore,the research on the hydrodynamic response of the new truss type aquaculture vessel has important engineering practical significance and can provide technical support for deep-sea aquaculture in China.Firstly,based on the potential flow theory,the frequency domain analysis of the large aquaculture vessel was carried out,focusing on the effect of water depth on the structural wave load and hydrodynamic parameters.The conclusion shows that the six-degree-offreedom response ampintude operators of the aquaculture vessel is influenced by the water depth,while the additional mass and other hydrodynamic coefficients are less influenced by the water depth variation.And then the effect of net clothing structure on the hydrodynamic characteristics of the breeding workboat is studied based on the concentrated mass method and the equivalent net clothing method.In the calculation,the anchor cable tension and hull dynamic response under four different working conditions,such as without truss and net,with truss but no net,with truss and single-layer net,and with truss and double-layer net,are analyzed by considering the uniform setting of eight anchor cables and cross-wave incidence.The results show that the increase of truss and netcoat has a greater influence on the motion of the aquaculture vessel and the tension of the chains,which should be considered in the process of mooring optimization.Finally,based on the configuration of single point mooring system,three different mooring methods are established,and the hull dynamic response curve and anchor cable dynamic tension under each working condition are obtained by time domain dynamic analysis,and the fatigue life of anchor chain under each working condition is calculated respectively.The results show that the mooring system with single anchor and two cables has higher safety and stability,and the mooring design can provide a reference basis for practical engineering.