As one of the most promising thermal management solutions, spray cooling has the advantages of high heat-transfer coefficient and maintaining a low temperature of the cooling surface. By summarizing the influential factors and practical applications of spray cooling, the current challenges and bottlenecks were indicated so as to prompt its potential applications in the future. Firstly, this paper reviewed the heat-transfer mechanism of spray cooling and found that spray cooling is more advantageous for heat dissipation in high-power electronic devices by comparing it with other cooling techniques. Secondly, the latest experimental studies on spray cooling were reviewed in detail, especially the effects of spray parameters, types of working fluid, surface modification, and environmental parameters on the performance of cooling system. Afterwards, the configuration and design of the spray cooling system, as well as its applications in the actual industry (data centers, hybrid electric vehicles, and so on) were enumerated and summarized. Finally, the scientific challenges and technical bottlenecks encountered in the theoretical research and industrial application of spray cooling technology were discussed, and the direction of future efforts were reasonably speculated.
16 December 2011 in Journal of Composite Materials
Joule’s first-law dictates that when electric current passes through a conductor heat is generated. The scope of this work is to investigate the Joule heating effect of two types of carbon fiber tows in dry form. The tows are used as primary heating elements on various preform structures that require accurate and uniform temperature control, using a DC power supply. The investigated temperatures, ranged from 300 K up to 650 K. A finite difference scheme was developed, in order to predict and quantify the transient phenomenon and is verified against experimental results. In order to exploit in-depth the phenomenon and achieve very good agreement between numerical and experimental results, temperature dependence of thermal and electrical properties (specific heat capacity, total hemispherical emissivity, and volume resistivity) was examined under controlled vacuum environment, ensuring no fiber oxidation.