三芯海底电缆中光纤与缆体应变关系的有限元分析方法

为了利用分布式光纤应变传感技术测量的光纤应变反映三芯光纤复合海底电缆的缆体应变,通过有限元方法进行了建模、求解和分析。通过合并导体屏蔽、绝缘屏蔽、半导体阻水层、填充层,忽略黄铜带、铠装垫层、外被层,对模型进行了简化;选用SOLID164单元对模型进行了动力学分析;施加匀速载荷对海缆进行了拉伸仿真试验。利用最小二乘法对铜导体、XLPE、铅护套、钢丝铠装与光单元的应变进行了拟合,获得了它们的函数关系式。模型求解结果满足弹塑性材料特性,可为研究海底电缆的力学性能、判断海底电缆工作状态提供参考。

Finite Element Analysis Method for Strain Relationship BetweenCable Body and Optical Fiber in Three-core Optical Fiber Composite Submarine Power Cable

In order to make use of the distributed optical fiber strain sensing technology to measure the strain of the three-core fiber composite submarine cable , the finite element method is used for modeling , solving and analyzing .The conductor screen, insulation screen, semiconductor resist layer and filling layer are merged to insulation layer .The model is simpli-fied and ignores the brass band , armored cushion and coating .The model is used to analyze the dynamics of the model by using the SOLID164 element.The uniform load is applied to the tensile simulation test .The strain of the copper conductor , XLPE, lead alloy, steel armor and optical unit is fitted by using the least square method , and their functions are obtained. The results of the model can meet the characteristics of elastic and plastic materials .It provides reference for the research of mechanical properties and judgment the operation conditions of submarine power cable .