JZUS-A - Journal of Zhejiang University SCIENCE A

Journal of Zhejiang University SCIENCE A
ISSN 1009-3095(Print), 1862-1775(Online), Monthly

2007 Vol. 8 No. 2 p. 197~204

On-line Access Date: Feb. 1, 2007

Metal hydride work pair development and its application on automobile air conditioning systems

QIN Feng^†1, CHEN Jiang-ping¹, ZHANG Wen-feng², CHEN Zhi-jiu¹

(¹Institute of Refrigeration and Cryogenic Engineering, Shanghai Jiao Tong University, Shanghai 200030, China)
(²Research Center, Zhejiang Yinlun Machinery Co., Ltd., Tiantai 317200, China)
^†E-mail: fqin@mail.sjtu.edu.cn
Received May 20, 2006 revision accepted Aug. 21, 2006

Abstract: Aiming at developing exhaust gas driving automobile air conditioning systems, a hydride pair LaNi_4.61Mn_0.26Al_0.13/ La_0.6Y_0.4Ni_4.8Mn_0.2 was developed working at 393~473 K/293~323 K/263~273 K. Property tests showed that both alloys have flat plateau slopes and small hystereses; system theoretical coefficient of performance (COP) is 0.711. Based on this work pair, a function proving automobile metal hydride refrigeration system was constructed. The equivalent thermal conductivities of the activated reaction beds were merely 1.1~1.6 W/(m∙K), which had not met practical requirement. Intermittent refrigeration cycles were achieved and the average cooling power was 84.6 W at 423 K/303 K/273 K with COP being 0.26. By altering cycling parameters, experiment data showed that cooling power and system COP increase with the growth of heat source temperature as well as pre-heating and regeneration time while decrease with heat sink temperature increment. This study confirms the feasibility of automobile metal hydride refrigeration systems, while heat transfer properties of reaction beds still need to be improved for better performance.

Key words: Metal hydride, Air conditioning, Reaction bed, Automobile, Coefficient of performance (COP)
doi:10.1631/jzus.2007.A0197 CLC number: TB6; TK91

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