The Study of PTFE Wicks Application to Loop Heat Pipes with Flat Evaporator

Abstract:

This study investigates the application of PTFE wicks to flat-plate loop heat pipes (FLHPs). PTFE’s low heat transfer coefficient effectively prevents heat-leakage, which is a problem with using metal wicks, lowering the operating temperature and pressure. This paper uses PTFE particles to form wicks, and the effect of PTFE on flat-plate LHP performance is investigated. Experimental results shows that the highest heat load reached was 100W, with lowest thermal resistance of 0.61°C/W, and heat flux of about 10W/cm², For the wick properties, the wick had an effective pore radius of the wick was around 9.2μm, porosity of 47%, and permeability of 1.0 x 10^-12m². Compared to the highest heat flux reported in literature thus far for PTFE flat-plate LHPs, the heat flux in this study was enhanced by around 50%.

• Periodical: Applied Mechanics and Materials (Volume 775)
• Pages: 54-58
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.775.54
• Online since: July 2015
• Authors: Shen Chun Wu, Shih Syuan Yan, Chen Yu Chung, Shen Jwu Su
• Keywords: FLHPs, PTFE, Wick

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