Finite Element Analysis Of Optical Fiber Composite Cable Submarine's Torsion And Wear Characteristics

Submarine cable is an important link to ensure the transmission and data communication between the islands and the islands,offshore platforms and offshore wind power supply,which plays an important role in the economic development of the society.Submarine cable was damaged by various external force in the complex geology of the seabed,which would not only affect the normal operation of the platform,but also lead to huge economic losses.At present,about mechanical characteristics of submarine cables were studied by some scholars,but there are few studies on the torsion and friction vibration.In this paper,the torsional and frictional vibration characteristics of submarine cables were studied by using the finite element method and built the relationship between the strain of the optical element in the submarine cable and the working stat us of the submarine cable,which provided theoretical support for monitoring the state of submarine cables using distributed optical fiber sensing technology.The structure of XLPE 110 KV composite submarine cable was analyzed.According to the operation environment and the material characteristics of each layer,the structure of the submarine cable was simplified.By using the finite element software ANSYS APDL language,a twisted structure was establish by the end section along the spiral line sweep mode.Finally,for realizing the finite element simulation of submarine cable torsion,the finite element model was applied torsion loads of different speed and direction and the influence of torsional velocity and direction on stress and strain of submarine cable was analyzed.In this paper,on the basis of ensuring the accuracy of the calculation,improving the computational efficiency,the finite element model of friction vibration of submarine cable was simplified.According to the actual environment of the friction between the submarine cable and the rock,the 3D model was simplified to two-dimensional.In the process of establishing the finite element model of friction vibration,selection of two dimensional element types,meshing,defining the contact pa irs and applying load finally,simulation of frictional vibration of submarine cable was finished.The vibration acceleration of light unit layer and steel wire armored layer at different locations was extracted and analyzed.