低温冷箱跑冷损失及其对内部换热器温度分布的影响  

Numerical simulation of thermal radiation in cold box and its influence on temperature distribution of heat exchanger

作　　者：余锋[1] 厉彦忠[1] 祝银海[1] 

机构地区：[1]西安交通大学能源与动力工程学院,西安710049

出　　处：《低温工程》2005年第6期15-19,共5页Cryogenics

基　　金：教育部跨世纪优秀人才基金;国家"十五"建设971工程项目

摘　　要：以中国先进研究堆(CARR)的冷中子源项目为背景,建立了低温换热器与冷箱换热的物理模型,并通过对换热器内部冷热流体之间的传热以及换热器与冷箱、管道、支架之间辐射换热的耦合计算,得出冷箱和换热器的辐射热流密度,以及辐射跑冷对冷箱内部换热器温度分布的影响。辐射跑冷导致换热器温度变化最高达4 K。采用铝箔包裹换热器和管道的隔热方法,可以大幅度减小辐射跑冷量。计算表明,运用该方法后辐射对换热器温度的影响最大不超过0.4 K,结果能够满足使用要求。A physical model of the heat transfer between heat exchanger and cold box has been built based on the practical engineering project of CARR-CNS. The simulation of the heat transfer between heat exchanger and cold box is conducted by coupling the thermal radiation and conduction. The radiation heat flux is obtained by calculation and the influence of temperature distribution of exchanger is also calculated. The maximal change of temperature of exchanger reaches 4 K because of influence of thermal radiation. In order to decrease the heat-loss of thermal radiation, an effective way is that the heat exchanger and conduit are wrapped by aluminum-foil. In this way, the maximal influence of thermal radiation is limited to less than 0.4 K, which meets the requirement of practical application.

关 键 词：冷中子源 真空 换热器 辐射 

分 类 号：TB657.5[一般工业技术—制冷工程] TB663