柔性立管内衬层的非线性力学行为分析  

Analysis of Nonlinear Mechanical Behavior of Flexible Riser Inner Liner

作　　者：刘军鹏[1] 张嘉毓 周雷[2] 段梦兰[1] LIU Junpeng;ZHANG Jiayu;ZHOU Lei;DUAN Menglan(College of Safety and Ocean Engineering,China University of Petroleum,Beijing 102249;Offshore Oil Engineering Co.,Ltd.,Tianjin 300450)

机构地区：[1]中国石油大学(北京)安全与海洋工程学院,北京102249 [2]海洋石油工程股份有限公司,天津300450

出　　处：《机械工程学报》2021年第20期89-97,共9页Journal of Mechanical Engineering

基　　金：国家重点研发计划(2018YFC0310504);国家自然科学基金(51809276)资助项目。

摘　　要：由于聚合物材料的黏弹性,柔性立管内衬层易发生蠕变而"嵌入"至骨架层沟槽中,这一现象可能造成立管结构完整性缺失和骨架层撕裂等安全隐患,但现有的分析理论及有限元模型中,对材料的性质均是做了简单的线性假设,并未考虑聚合物材料的非线性黏弹性特性。基于PA11的试验测试结果,分别采用时间硬化非线性本构模型和考虑时温影响的多重积分非线性本构模型来表征材料性质,并对比两种模型与试验数据拟合情况。根据内衬层与骨架层的真实结构建立二维有限元数值模型,采用两种理论模型进行结构的非线性蠕变行为分析及对比。结果表明:非线性蠕变本构模型能够在在非稳态阶段和存在温度梯度的条件下,更加准确地预测的结构关键部位应变和应力,可为柔性立管内衬层的设计及评估提供借鉴和参考。Due to the viscoelasticity of polymer materials, flexible riser inner liner creep and prone to “embedded” into the carcass grooves, this phenomenon causes loss of structural integrity and carcass layer tear, etc., but in the existing analysis of theory and finite element model, the nature of the material are made a simple linear hypothesis, did not consider nonlinear viscoelastic properties of polymer materials. Based on the experimental test results of PA11, the time-hardening nonlinear constitutive model and the multi-integral nonlinear constitutive model considering the effect of time temperature are used to characterize the material properties respectively, and the fitting of the two models with the experimental data is compared. Based on the real structure of the inner liner and the carcass layer, a two-dimensional finite element numerical model is established, and the nonlinear creep behavior of the structure is analyzed and compared by using the two theoretical models. The nonlinear creep constitutive model can predict the strain and stress of the key parts of the structure more accurately in the unstable stage and under the condition of temperature gradient,which can provide reference and reference for the design and evaluation of the inner liner of flexible riser.

关 键 词：柔性立管 内衬层 聚合物黏弹性 蠕变 有限元模型 

分 类 号：O345[理学—固体力学]