周期性非稳态传热对低温容器的影响机理及实验

对低温容器分别在环境温度下和有外热源条件下进行热响应实验,发现低温容器静态蒸发率呈周期性变化,但变化周期仅为环境温度变化周期的1/2,环境温度的周期性变化并非是使高真空多层绝热容器蒸发率测量时产生周期变化的主要因素。在进行外热源加热容器外壁实验时发现,外壁温度变化并没有对低温容器的漏热量产生明显的影响,低温容器的绝热层对低温容器外壁面的温度波动有较强的衰减及延迟作用,热量在传入的过程中发生了剧烈的衰减,使容器内壁近似形成一个"等温层",从而使高真空多层绝热低温容器的漏热量几乎不受外界环境温度变化的影响。

Mechanism and experiment for influence of periodic unsteady state heat conduction on cryogenic vessel

The evaporation rate of a cryogenic vessel was measured in environment temperature and with exterior heat source respectively.It was found that the evaporation rate of cryogenic vessel presented periodic change,but the change period was only half of the periodic change of environment temperature,the period of environment temperature was not a main factor of the periodic change of cryogenic vessel's evaporation rate.At same time,the temperature change of outside wall had no obvious influence on the heat leak...