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http://dx.doi.org/10.9714/psac.2006.8.1.065

Thermal diffusion experiment of impulsive heat in subcooled liquid nitrogen  

Choi, J.H. (홍익대학교 기계시스템디자인공학과)
Ha, J.C. (홍익대학교 기계시스템디자인공학과)
Byun, J.J. (홍익대학교 과학기술연구소)
Chang, H.M. (홍익대학교 기계시스템디자인공학과)
Kim, H.M. (LS산전 전력연구소)
Ko, T.K. (연세대학교 전기전자공학부)
Publication Information
Progress in Superconductivity and Cryogenics / v.8, no.1, 2006 , pp. 65-70 More about this Journal
Abstract
Transient heat transfer caused by an impulsive heating in subcooled liquid nitrogen is investigated experimentally. This study is part of out ongoing efforts directed to a stable cryogenic cooling system lot superconducting fault current limiters (SFCL). A thin heater attached by epoxy on one surface of a GFRP plate is immersed in liquid-nitrogen bath at temperatures between 77 K and 55 K. A strong heat flux up to $150W/cm^2$ is generated lot 100 ms, and the temperature of the heater sulfate is measured as a function of time. The behavior of bubbles on the heating surface can be explained by comparing the measured temperature history for vertical and two horizontal (up and down) orientations. It is concluded that the subcooling of liquid nitrogen below 70 K is very effective in suppressing bubbles, resulting in better thermal protection and faster recovery from an impulsive heat.
Keywords
Heat transfer; Subcooled liquid nitrogen; Impulsive heat; Fault current limiter;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
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