| The object studied of this paper is the verification system of mining technology in the Twelve-Five project of the Ocean Mineral Resource Research and Development Association’s "Development and Integration of Polymetallic Nodule Collecting System Facing Sea Test",the system is composed of three parts:mining vessel,composite cable and collector.On the basis of the theory of multi-rigid body dynamics,the virtual prototype model of the polymetallic nodule mining system was established,and the configuration design of the composite cable operaion and dynamic simulation analysis of the overall linkage were performed,which provided data support for the sea test of the mining system.The main study contents and positive result of this dissertation are as below:By comparing the dynamic analysis methods of three pipeline structures,the mathematical expression of the equivalent spring between the discrete composite cable elements is derived from the application of the multi-rigid discrete element in the space beam,according to the properties of composite cables and float ball,the various marine environmental loads to which the mining system is exposed and the boundary conditions,design and analysis of the operation configuration of the composite cable based on the position and number of floating ball arrangements and the horizontal distance of the ship’s plane,and the arrangement scheme of floating ball on the composite cable is determined.According to the overall linkage of the mining system and the constraint relationship between the each system,the mining system simulation models of 500m deep sea depth and 50m deep sea depth are established based on virtual prototype technology.Aiming at the 500m sea trial mining system.The length of the composite cable,the arrangement and quantity of float ball and so on are analyzed according to the scope of the collector operation.The design and optimization of the space configuration of the composite cable,the ideal double-arch saddle configuration is obtained,and which verifies the feasibility of the design.The effects of different mining width,different mining gap and different mining speed on the spatial configuration and dynamic behavior of the 500m sea test mining system are studied under the lateral reciprocating motion operation mode respectively.The simulation results show that the larger the mining width,the larger the force on the mining vessel and the collector,the maximum value is reached at the farthest distance from the mining vessel,and the more unstable the dynamic characteristics of the mining system.The change of mining gap has little effect on the forces received by the mining vessel and the ore collector,but the bigger the mining gap,the greater the mutation value in the force of the mining machine at the turn.The greater the mining speed,the shorter the mining system takes to carry out the mining operation in one cycle and the higher the efficiency of the ore collecting operation.However,the greater the total force is exerted on the ore collector,the more unstable the dynamic characteristics of the mining system.On the basis of the research method of 500m sea trial system,two models of shallow water test are studied.one is the collection model design and the linkage control analysis of composite cable length of 80m,The other is the collection model design and linkage control analysis of the composite cable length of 250m.The simulation results show that the single-arch configuration formed by the mining system with the length of 80m of composite cable is more favorable to the seabed ore gathering operation.The double-arch configuration of the 250m composite cable length mining system is more favorable to seabed mining operation.The mining system with a composite cable length of 80m and 250m in the lateral reciprocating motion operation of the entire cycle of the design trajectory,The composite cable can present good spatial configuration and the overall linkage process of the mining system is stable. |
PDF Full Text Request