柔性管骨架层压溃简化数值模型研究  

Study on Simplified Numerical Models to Predict Collapse for Carcass Layer of Flexible Pipes

作　　者：廖舒婷 黄小平[1] 孙力 周涛 LIAO Shuting;HUANG Xiaoping;SUN Li;ZHOU Tao(State Key Laboratory of Ocean Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)

机构地区：[1]上海交通大学海洋工程国家重点实验室,上海200240

出　　处：《中国造船》2022年第3期135-148,共14页Shipbuilding of China

摘　　要：柔性管骨架层是截面形式复杂的自锁螺旋结构。若考虑材料、几何和接触等非线性,则计算复杂且有时不收敛,因此引入简化数值模型来研究骨架层压溃是一种有效的方法。目前常采用计入骨架层实际截面形状的1/4对称环模型,对不同缠绕螺旋角的骨架层压溃问题研究尚未见报道。论文从等效刚度理论出发,利用有限元软件ANSYS,提出了用于两种用于骨架层数值计算的简化模型,即单圈螺旋条带模型和等效矩形截面螺旋条带模型,并基于两种简化模型探究了几何、材料非线性和螺旋角对骨架层压溃的影响。结果表明:两种简化模型都能有效模拟骨架层的压溃行为。其中等效矩形截面螺旋条带模型由于没有层间接触,在非线性分析中极大地提高了计算效率。骨架层的临界压力值随着螺旋角的增大而增大,但当螺旋角大于80°时可以不考虑其对骨架层压溃的影响。本文结果可为柔性管骨架层的优化设计提供支撑。Carcass layer of flexible pipe has a self-locking helical structure with complex cross-section.If material,geometry and contact nonlinearity are considered,the calculation will be complicated and sometimes not convergent.Therefore,it is an effective method to study the collapse of the carcass by introducing a simplified numerical model.At present,a 1/4 symmetrical ring model with the actual cross-sectional shape is often used.There have been no reports so far on the collapse of the carcass at different helix angles.In this paper,based on the equivalent cross-section theory,two simplified numerical models of the carcass layer are established by using the finite element software ANSYS.The first model is a single-circle spiral strip and the second one is a spiral strip with equivalent rectangular section.Effects of geometry,material nonlinearity and the helix angle for the collapse of the carcass are studied.The results show that the two simplified models can effectively simulate the collapse behavior of the carcass layer,in which the rectangular section strip has no interlayer contact,greatly improving the computational efficiency in the nonlinear analysis.The critical pressure value of carcass increases with the increasing of the helix angle.When the helix angle is greater than 80 degrees,its influence can be ignored.The conclusions of this paper may provide supports for the subsequent optimization design of carcass layer.

关 键 词：骨架层 压溃 简化数值模型 矩形截面 螺旋角 非线性 

分 类 号：P756.2[天文地球—海洋科学]