| Summary: | 碩士 === 國立成功大學 === 機械工程學系 === 102 === On account of the threatening depletion of crude oil, it is imperative to find an alternative energy for sustainable development, and metal hydride system appears to be the most promising one to fossil fuels among all current options because of its high calorific value and environmentally friendly characteristics. A series of theoretical and numerical works were done in our group to analyze the heat and mass transfer phenomena happening in the reactor. Furthermore, the adsorption/desorption process is a reversible endothermic/exothermic reaction, so heat transfer properties of hydrogen storage system would affect the efficiency directly and must therefore be carefully managed. Due to simplicity and safety concerns, and for fundamental understanding of the underlying thermofluid mechanisms, experiments of this thesis are carried out by silica gel instead of metal hydrides. Furthermore, silica gel is a porous medium in essence, hence the present work is devoted to experimental performance analysis of thermal management for porous reactors, especially in analyzing the effects on adsorption/desorption efficiency of heat transfer enhancement mechanism such as axial heat exchanger with longitudinal fins. The major results are briefly presented: the adsorption efficiency has an 18.75% improvement by equipping an axial heat exchanger with 8 longitudinal fins on the reactor, and the system is able to adsorb more water in the cases of higher humidity, larger flow rates of air and coolant. On the other hand, the efficiency in dehumidification is improved by heating the air to higher temperature and letting more air access to the reactor. To conclude, the contribution of this work is not only in easing energy crisis, but also applying to improvement of technologies in various aspects.
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