Heat transfer investigation of a flat-plate oscillating heat pipe with tandem dual channels under nonuniform heating. (December 2021)

• Record Type: Journal Article
• Authors: Chen, Xi; Chen, Shengkai; Zhang, Ziwen; Sun, Dongke; Liu, Xiangdong
• Is Part Of: International journal of heat and mass transfer. Volume 180(2021)
• Publication Date: 2021-12
• Subjects: Flat-plate oscillating heat pipe -- Nonuniform heating -- Tandem dual-channel structure -- Multiple heat sources and sinks -- Thermohydrodynamic performance; Heat -- Transmission -- Periodicals; Mass transfer -- Periodicals; Chaleur -- Transmission -- Périodiques; Transfert de masse -- Périodiques; Electronic journals; 621.4022
• DOI: 10.1016/j.ijheatmasstransfer.2021.121830
• Languages: English
• ISSNs: 0017-9310

Abstract

Highlights: A novel tandem dual-channel flat-plate oscillating heat pipe (OHP) is tailored and fabricated. Thermo performance of the flat-plate OHP under nonuniform heating are experimentally studied. Influences of nonuniform heating degree coupled with heat load and inclination angles are clarified. Flat-plate OHP works with 15.3% thermal resistance of a pure 6063 aluminum alloy plate along 101.8 mm. Flat-plate OHP has a fine gravity adaptability over wide operating conditions under nonuniform heating. Abstract: To provide cooling of electronics under nonuniform heating from multiple heat sources, a novel tandem dual-channel flat-plate oscillating heat pipe (OHP) is tailored and experimentally studied with a "center-multiple-heat-source nonuniform heating and two-end air cooling" layout under different inclination angles, heat loads and nonuniform heating levels. Flow pattern diagrams together with thermal resistance contour maps are organized for two tandem mirror-symmetric halves of the flat-plate OHP, and the thermal performance differences under nonuniform and uniform heating are compared. It is indicated that, compared with uniform heating, nonuniform heating produces better thermohydrodynamic performance at a low heat load with quasi-steady "stop-oscillation" fluid motion in the flat-plate OHP, while it results in poorer thermohydrodynamic performance when the heat load is large enough to maintain sustainable fluid flow in the flat-plate OHP. Under nonuniform heating conditions, concentrating more heat to overcome the negative effects rather than to amplify the positive effects on the fluid flow and heat transfer in OHPs is more beneficial to the overall thermal performance. For the 540 tested conditions, the flat-plate OHP has a much smaller overall thermal resistance than a pure 6063 aluminum alloy plate with the same configuration (approximately 15.3% on average) along a heat transfer distance of 101.8 mm. In addition, it possesses good adaptability to gravity, with coefficients of variation of 27.6% in the overall thermal resistance for inclination angles from 0° to 90°. Accordingly, this flat-plate OHP has good potential for high-efficiency and good-adaptability cooling of electronics under nonuniform heating by multiple heat sources.