高空真多层绝热低温管道中波纹管简化有限元模拟方法  

A simplified finite element simulation method of bellows used in HV-MLI cryogenic pipes

作　　者：毛红威 陈叔平[1] 杨佳卉 金树峰[1] 张军辉[2] 苏海林[2] Mao Hongwei Chen Shuping Yang Jiahui Jin Shufeng Zhang Junhui Su Hailin(School of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050,China Institute of Modern Physics, Chinese Academy of Sciences,Lanzhou 730000,China)

机构地区：[1]兰州理工大学石油化工学院,兰州730050 [2]中国科学院近代物理研究所,兰州730000

出　　处：《低温工程》2016年第5期64-70,共7页Cryogenics

基　　金：甘肃省科技重大专项"大型LNG贮罐研发"(1203GKDA001)资助

摘　　要：基于有限元方法对高真空多层绝热(HV-MLI)低温管道进行多场耦合分析时,由于内管道波纹管几何及材料的非线性特性,使整个分析过程极为耗时,限制了有限元法在HV-MLI低温管道优化设计中的应用。为提高有限元分析效率,结合HV-MLI低温管道对所受载荷的响应特征,提出了用Combine14弹簧单元或等截面管等效替代波纹管的方法。通过对Combine14弹簧单元和等截面管相关参数的理论计算及定义,建立了两种HV-MLI低温管道内管的等效有限元计算模型,并对含波纹管、Combine14弹簧单元及等截面管内管道模型分别进行了有限元模拟计算,得到了各模型内管的应力及变形结果。结果表明:建立的两种等效模型合理、有效;与含波纹管模型相比,两种等效模型均在保证分析精度的同时,将分析效率提高了300倍;相比含Combine14弹簧单元模型,含等截面管模型在结构不连续处的应力集中程度较轻,且与含波纹管模型相符,更适于HV-MLI低温管道的多场耦合分析。The multi-field coupling finite element analysis of bellows used in the inner tube of HV-MLI cryogenic pipes is very time-consumed, because of the nonlinear calculation of material and structure, which becomes an obstacle to the application of FEM in the optimal design of HV-MLI cryogenic pipe. In order to improve the analysis efficiency of the FEM, a bellows equivalent method was presented based on the response characters of HV-MLI cryogenic pipe under the loads. In this method, Combine14 spring element or equal-section pipe was used to replace the bellows. Two equivalent finite element models of the inner tube of HV-MLI cryogenic pipes were established by calculation and definition of relevant parameters of Combinel4 spring element and equal-section pipe, the stress and deformation of inner tube in each model was calculated by numerical simulation of the inner tube models which include bellows, Combine 14 spring element and equal-section pipe respectively. The results show that： the two equivalent models are reasonable and effective, the efficiency of equivalent models increases is 300 times than that of the model contained bellows without decreases the accuracy of simulation. Compared to the model with Combine 14 spring element, the stress concentration of the model with equal-section pipe is lower in the discontinuous region of structure, whith is correspond with the model with bellows. Therefore the model with equal-section pipe is more suitable for the multi-field coupling analysis of HV-MLI cryogenic pipe.

关 键 词：低温管道 波纹管 有限元等效方法 

分 类 号：TB657[一般工业技术—制冷工程]