铜表面涂敷环氧绝缘漆在LHe中传热研究

HEAT TRANSFER CHARACTERISTIC OF COPPER SURFACE COATING WITH EPOXY IN LIQUID HELIUM

对大面积高纯铜５０ｍｉｎＸ１０ｍｍ×４ｍｍ试样，表面涂敷环氧绝缘漆，在一个大气压饱和ＬＨｅ中进行传热性能研究。同光滑铜试样传热比较，测量液氦核沸腾临界热通量（ｑｃＨＦ）、膜沸腾最小热通量（ｑＭＨＦ）、导热系数及其随散热角度变化。实验表明钢表面涂敷环氧绝缘漆后，其核沸腾临界热通量、膜沸腾最小热通量都增加，导热系数减小近１／３，且试样不论水平放置、垂直放置其核沸腾曲线都向右偏移。

The heat transfer of coating copper plats (50 mm X 10 mm X 4 mm)in saturated liquid helium at atmospheric pressure has been measured as a function of orientation, and comparing their critical heat flux (9CHF) in nucleated boili ng, minimum heat flux (qMHF) in film boiling with polished copper. The results show the coating epoxy coppers' qCHF, qMHP have Increased,but their heat transfer coefficient for nucleate boiling decreased about three times. The qCHF depended on the surface orientation, and the qMHF did not so. At sometime the nucleate boiling cureshifted to a higher superheat region whether the plates were placed horizontally or vertically.