摘要
提出一种"空间冷屏蔽系统"模型,通过空间深冷剂的相变制冷可使空间飞行器表面温度低于100 K,30 min内使表面红外辐射强度低于0.5 W/m2;进而建立三维气液分离储液模型,并对分层储液结构进行单元传热数值模拟,分析单元模型的不同传热边界条件,将换热经验关联式应用于稳态传热数值模拟过程,从而获得冷屏表面温度及热流随液位变化的分布规律;然后建立单元实验模型并进行实验分析.模拟计算及实验结果表明:当分层储液高度小于100 mm时,实验温度梯度与数值模拟结果相似;实验系统的表面温度在地面15 min以内、空间30 min以内可以满足低温红外辐射特征要求;太阳能辐射强度和毛细材料对表面温度分布的均匀性及液氮维持时间有一定的影响.
A technique about spatial cold shield system with phase-change refrigeration by the cryogens is presented to lower the surface temperature of a spacecraft under 100 K, furthermore to lower the infrared radiation on the spacecraft under 0.5 W/m^2 in 30 minutes, then a 3-D layered reservoir model is established for the simulation of heat transfer. In this simulation process, the empirical equations are substituted to boundary conditions of stable heat-transfer relations to simulate the surface temperature and heat flux changing with the liquid level. Then an experimental unit model is constructed for process analysis. The simulation and experiment results show that the experimental temperature gradients are similar to the simulation results before the exhaustion of liquid nitrogen when liquid level of layered reservoir is less than 100 mm; surface temperature of the system meets the requirement of infrared radiation in 15 min on the ground and 30 min in the space; solar radiation and capillary material influence the uniformity of surface temperature and holding time of liquid nitrogen to some degree.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
2009年第8期116-124,共9页
Journal of Xi'an Jiaotong University
基金
中国航天科技集团公司预研资助项目(617010303)
关键词
冷屏蔽系统
红外辐射
相变制冷
液氮
cold shield system
infrared radiation
phase-change refrigeration
liquid nitrogen
