摘要
为验证微细通道内流动沸腾散热技术在空间的适用性,用实验方法研究了平行微细通道内流动沸腾换热的重力无关性。搭建了两相流体回路系统,设计了水力直径0.91mm、倒梯形截面的平行微细通道铜基热沉,通过电火花腐蚀技术在铜基加热器表面刻蚀制作微细通道,两者集成一体。由实验分析了-90°~90°不同重力倾角下微通道内的流动沸腾特性。结果发现:不同流量下不同重力倾角的微细通道的沸腾曲线基本吻合,临界热流值基本一致,表明微通道不仅强化换热能力,而且削弱了重力对沸腾换热的影响。实验结果处于文献中Bo准则和Fr准则的重力无关性区域内,验证了微细通道内流动沸腾换热具一定程度的重力无关特性,地面上测得的微通道内流动沸腾换热系数和临界热流等实验数据能安全有效用于空间环境的热控设计。
In order to check the applicability of flow boiling heat transfer in micro/mini-channels techniques in space,a fluid loop test system was applied to investigate the gravity independence in parallel micro/mini-channels heat sink in this paper.The two-phase loop system was built up.The copper heat sink with hydraulic diameter0.91 mm and inverted trapezoidal section was designed.The micro/mini-channels were made on the surface of the sink using spark erosion,which was integrated with the sink.The boiling heat transfer characteristics under different gravity orientations from-90°to 90° were discussed by the test.It was found that flow boiling experiments with various flows under different gravity orientations exhibited almost the same boiling curve and critical heat flux(CHF)values,which meant that the micro/mini-channels could not only enhance the heat transfer but also weaken the effect of gravity on the boiling heat transfer.The test results were in the gravity independence area of the Bo criterion and Fr criterion in the references.The experimental data with gravity independence criteria from references verified further that flow boiling heat transfer in micro/mini-channel was somewhat gravity independence,and the experimental data including flow boiling transfer coefficient and CHF of the micro/minichannels measured on the ground could apply in design of the thermal control system in space.
出处
《上海航天》
2016年第3期118-123,共6页
Aerospace Shanghai
基金
国家自然科学基金资助(51406122)
中国博士后基金资助(2014M561459)
863重大专项课题(2013AA8073034)
关键词
微细通道
两相流体回路
流动沸腾
换热
重力无关
热沉
临界热流
Bo准则
Fr准则
Micro/mini-channels
Two-phase loop
Flow boiling
Heat transfer
Gravity independence
Heat sink
Critical heat flux
Bo criterion
Fr criterion
