直角型高真空多层绝热低温管道热结构耦合分析

Thermal-structure coupled analysis of right-angle cryogenic pipeline with high-vacuum multilayer insulation

纵横交错的低温管路系统中,直角型低温管道使用是不可避免的,由于直角型低温管道结构的特殊性,其热应力分布不同于直管。借助ANSYS Workbench 13.0有限元分析软件,对某低温管路系统一段直角型高真空多层绝热低温管道进行稳态热结构耦合分析,并对最大热应力进行校核。结果表明:绝热结构满足保冷要求,有效减小了管壁热应力;支撑是主要的传热路径,与内外管接触位置附近温度梯度比较大;支撑热应力主要分布在与内外管接触的对角线周围,分布位置呈现对称的特征,最大热应力发生在与内管接触处,值为62.631MPa;内外管热应力主要发生在1200mm的水平内管壁上靠近管口位置,最大热应力为31.075MPa;对内外管和支撑最大热应力进行相应校核,证明该管道是安全可靠的。对同类型低温管道结构设计及支撑位置和数量合理设置具有重要参考价值,同时对低温管道安全运行具有重要意义。

In the crisscross cryogenic tube system, the application of right - angle cryogenic tube is inevitable, and because of the particularity of right - angle cryogenic tube, the thermal stress distribution is different from straight cryogenic tube. Based on the ANSYS Workbench 13.0 finite element analysis software, the steady - state thermal - structure coupled analysis of one right - angle cryogenic tube with high vacuum muhilayer insulation in certain cryogenic tube system was carried on and the maxi- mum thermal stress was checked. The result shows that the heat insulation structure meets the requirement and effectively reduces the tube wall thermal stress ; the strut is the main heat transfer path and the temperature gradient near the contact position of in- side and outside tube is more obvious ; the strut thermal stress mainly symmetrically distributes around the diagonal of the contact position of inside and outside tube and the maximum thermal stress occurs in the contact position of inside tube and is 62. 631MPa; the thermal stress of inside and outside tube mainly occurs near the nozzle position of 1200 mm horizontal inside tube wall and the maximum thermal stress is 31. 075MPa; the maximum thermal stress of inside and outside tube and strut are checked and the safety and reliability of this tube are proved. The analysis result can provide an important reference for the structure design and the reasonable settings of strut position and quantity of the same type cryogenic tube, and has great significance on the safe operation of cryogenic tube.