臺灣博碩士論文加值系統

摘 要
蒸發式冷凝器的優點有可應付大散熱容量冷凝器的負載需求，減小冷凝器構造尺寸，並提升空調機之性能。一般空調設備採用蒸發式冷凝器的基本構造是利用灑水裝置把水淋在冷凝器盤管的裸管上，冷凝器的風扇鼓動空氣流過冷凝器盤管，冷凝器盤管的裸管表面上水膜與空氣產生熱質傳作用，將冷凝器的冷媒熱量藉蒸發水份由空氣帶走；本研究實驗之蒸發式冷凝器是採用改良型之蒸發式冷凝器，在蒸發式冷凝器之銅管上包覆一層吸水性材料，利用吸水性材料的吸水特性，能有效的吸住水份使冷凝器之銅管表面常保潤濕，以維持良好的熱質傳作用，而不需要持續灑水，因此可節省用水之消耗，甚至可免除灑水水泵之裝設（利用自來水水壓灑水），而省掉水泵之消耗功率及保養維修。
本研究實驗之機器設備為冷房能力5600 kcal/hr(6.5 kW)之一對一分離式空調機，是採用銅管包覆一層吸水性材料的蒸發式冷凝器，研究實驗之對象即為此型式之蒸發式冷凝器，研究內容主要為探討此型蒸發式冷凝器之熱質傳性能，吸水性材料的含水量及對熱質傳性能的影響，吸水性材料含水量的補充時機；實驗結果與理論模式之預測值經分析比對，發現此型蒸發式冷凝器在吸水性材料最大含水量的75％∼80％之內時，熱質傳性能實驗值與預測值在變化趨勢上頗為吻合，此時空調機運轉之功率消耗幾乎不變，因此蒸發式冷凝器應在吸熱蒸發75％∼80％之最大含水量後，補充吸水性材料的含水量，如此才可維持蒸發式冷凝器的熱質傳性能，使空調機之運轉功率消耗最少，而達到省能的效果。

Abstract
The evaporative condenser has an obvious effect on energy saving. The evaporative condenser used in this study was wrapped with a layer of water-absorbing material on the copper tubes of the condenser. The wrapping material absorbs water effectively to keep wetting the surface of copper tubes, which could maintain good heat and mass transfer performance without spraying water continuously to reduce the consumption of water. In addition, the water pump could be void to save the cost of power consumption and maintenance.
The test machine used in this study is a 5600 kcal/hr (6.5 kW) one to one split type air conditioner with evaporative condenser whose copper tubes were wrapped one layer of water-absorbing material. The aims of this experiment are to study the heat and mass transfer performance of this kind of evaporative condensers, the effect of water content in water-absorbing material on the heat and mass transfer performance and the timing of water supply for water-absorbing material. The experimental results were compared to the predicted values obtained from theoretical model. It is found that the experimental data of heat and mass transfer performance matched well with the predicted values and also the power consumption of air conditioner is with little change while the water-absorbing material’s water content is within the range of 75 to 80% to its maximum. Therefore, it is concluded that supply of water for water-absorbing material is necessary when 75 to 80% of its maximum water content has evaporated. It would make evaporative condenser keep good heat and mass transfer performance; minimize the power consumption of air conditioner to have the energy saving effect.

目 錄
摘 要iii
誌 謝v
目 錄vi
圖目錄viii
表目錄xi
符號說明xii
第一章 緒論1
1.1前言1
1.2研究背景2
1.3文獻回顧4
第二章 研究動機與目的6
2.1各式冷凝器基本功能分析6
2.2研究動機11
2.3研究目的12
第三章 研究內容與方法14
3.1研究內容14
3.2實驗設備與量測裝置之建構15
3.2.1實驗設備之建構15
3.2.2量測裝置之建構16
3.3實驗流程24
3.4理論分析26
3.4.1平均對流熱傳係數 的計算26
3.4.2空氣與蒸發式冷凝器銅管濕表面之熱質傳29
3.4.3通過蒸發式冷凝器的冷卻空氣出口狀態之分析32
3.4.4蒸發式冷凝器吸水性材料含水量之影響35
第四章 結果分析與比較40
4.1蒸發式冷凝器的傳遞單位數NTU40
4.2蒸發式冷凝器冷卻空氣出口狀態之比較分析43
4.2.1蒸發式冷凝器冷卻空氣出口狀態實驗值之求法43
4.2.2蒸發式冷凝器冷卻空氣出口狀態預測值之求法44
4.2.3蒸發式冷凝器冷卻空氣出口狀態實驗值與預測值之比較分析45
4.3吸水性材料含水量對消耗功率之影響68
4.4吸水性材料含水量之分析73
第五章 結論83
5.1研究結論83
5.2研究貢獻與建議84
參考文獻86

參考文獻
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