矽膠塗佈厚度對扁平管吸附床性能之影響

The influence of performance of flat-tube adsorption bed by the thickness of silica gel coated layer

林宗漢(Zong-han Lin)

指導教授 ： 楊建裕

國立中央大學/工學院/機械工程學系/碩士(2011年)

摘要

本實驗使用矽膠-水做為工作配對，以扁平管做為吸附式空調系統中之吸附床，希望改進現有吸附床缺點，以期達到高填充量與低熱阻之吸附床，並採用塗佈式設計，增加吸附床性能。另外針對不同矽膠塗佈厚度做研究，分析不同塗佈厚度對於吸附床性能之影響，找出最佳塗佈厚度。
實驗結果發現，相較於圓管式吸附床，扁平管式吸附床在使用相同的腔體容積下有較多的矽膠填充量與較好的吸附性能。而在塗佈厚度的分析，薄塗佈厚度之矽膠層有比較小的熱阻以及較佳的質傳性能，因此在較少的矽膠量下仍有較好的吸附性能與冷凍能力。

關鍵字

厚度 ； 吸附式製冷 ； 吸附床 ； 矽膠-水

並列摘要

An investigation of adsorption bed using flat-tube in a adsorption cooling system with siliga gel as adsorbent and water as refrigerant is described. The new type adsorption bed is in order to increase the amount of adsorbent and decease the thermal resistance. Otherwise, the performance of the adsorption bed with difference thickness of silica gel coated layer on the flat-tube is discussed.
The results show that the performance of the flat-tube adsorption bed is better than the circular tube. The amount of water adsorbed of flat-tube adsorption is 2.2 times than the circular tube in 10 minutes at adsorption cycle. Otherwise, it is smaller thermal resistance and better performance of mass transfer by thin thickness of silica gel coated layer. It means that the 2.8 mm coated layer has better performance of adsorption and cooling power.

並列關鍵字

thickness ； adsorption cooling ； silica gel-water ； adsorption bed

參考文獻

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