多层绝热和支撑辐射对低温传输管线的影响分析

Analysis of effects of multi-layer insulation and support radiation on cryogenic transfer lines

为了确保低温传输管线的设计质量,采用高真空多层绝热方式减少管线的漏热。通过分析多层绝热和支撑表面辐射,对低温传输管线进行了传热模拟研究,得到了内管道壁面间的辐射换热量和支撑总体漏热量。分析了三角形和正方形支撑漏热量的不同;同时对比了不同发射率支撑表面下,支撑辐射换热量、导热量和温度分布的变化。结果表明:在满足支撑强度条件下,应当增大热传导距离,减小支撑的接触面积以及辐射换热面积;随着支撑表面发射率增大,支撑表面辐射换热量增加,导热量减少,总体漏热量增大,当发射率为1时,模拟得到的漏热量仍小于1 W/m。

In order to guarantee the good quality of transfer lines,multi-layer insulation was used to reduce heat leak in the lines.The thermal simulation of the cryogenic transfer lines were made by analysis of the multi-layer insulation and support radiation,by which the radiation heat transfer of the pipe wall were obtained.Meanwhile,the heat leak of triangle and rectangular supports were analyzed.In addition,under different emissivity of support surfaces,the radiation heat transfer,conduction heat transfer and temperature distribution of support were also observed and compared.The results showed that,in order to reduce the heat leak,under the intensity of support is satisfy,the support area of contact and radiation should be reduced,the distance of conduction heat transfer should be increased.With the increase of emissivity of support surface,the radiation heat transfer and the overall heat leak of support surface increased,while conduction heat transfer of support decreased.When the emissivity is 1,the heat leak is less than 1 W/m.