冷藏展示櫃應用間接蒸發式冷凝器之節能效益分析

Investigation of Energy Saving Potential for Reach-In Refrigerator Using Indirect Evaporative Condensers

陳易青(Yi-chin Chen)

指導教授 ： 柯明村

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2005年)

https://doi.org/10.6841/NTUT.2005.00052

摘要

蒸發式冷卻是一種非常有效的排熱技術，採用間接蒸發式冷凝器能有效提升冷凍機的散熱能力。間接蒸發式冷凝器除了與直接蒸發式冷凝器具有相同的高排熱效率外，還可改善以水冷式或直接蒸發式運轉時所產生的水源浪費與預防退伍軍人症發生，對於周圍環境也無熱污染等問題。然綜觀目前國內外之冷凍冷藏展示櫃甚少採用間接蒸發式冷凝器作為排熱裝置。因此本研究嘗試將間接蒸發式冷凝器與商用冷藏展示櫃作結合，以期能獲得較佳的省能效率。
藉由實驗結果之數據分析，可求得間接蒸發式冷凝器於間接蒸發冷卻模式與氣冷模式之運轉效率，並找出最佳之運轉模式與水牆最佳補給水量時機。另外利用模擬方法探討，改變入口乾球溫度、相對濕度以及水牆厚度與入口風速等參數，來瞭解對間接蒸發式冷凝器散熱能力之影響。最後以量測實驗值與理論分析的預測值比對其出口冷卻空氣之狀態，驗證熱質傳遞之熱交換性能。
由研究結果得知，間接蒸發式冷凝器運轉於間接蒸發模式時之性能係數比氣冷模式下可提升1~25 ％。而間接蒸發模式下運轉之壓縮機消耗功率可比氣冷模式下之壓縮機消耗功率低5~7.8 ％。另外系統運轉於冷凝壓力為1280 kPa時，間接蒸發式冷凝器具有最高的運轉效率。

關鍵字

間接蒸發式冷凝器 ； 水牆 ； 鰭管式熱交換器

並列摘要

Evaporative cooling is one of very effective heat transfer technologies. Using the indirect evaporative condenser can effectively improve the heat transfer ability of refrigerating machine. The indirect evaporative condenser not only can keep the higher heat transfer efficiency corresponding to direct evaporative condenser but also can avoid waste water and prevent the Legionellosis infected while using water cooling or evaporative cooling. Besides, it has no thermal pollution to the surrounding environment. Nowadays the Reach-In refrigerator seldom uses indirect evaporative condenser as its heat transfer device. Therefore, we try to combine Reach-In refrigerator with indirect evaporative condenser in this study and expect to get the better energy saving efficiency.
With the experimental results, the operation efficiency can be obtained in both indirect evaporative cooling type and air cooling type systems also the optimal type of operating condition can be found out. Moreover, the simulated method developed in the present study has been used to investigate the relationships between indirect evaporative condenser capacity and process variables such as inlet dry bulb temperature, relative humidity , thickness of Evaporative Section and inlet air velocity. In addition, by comparing the experimental data with the theoretical analyzed results in the outlet air condition has been performed and the heat and mass transfer performance was also verified.
Experimental results show that the coefficient of performance (COP) using indirect evaporative cooling type can be enhanced about 1 to 25 % compared to the air cooling type, and the compressor power consumption also can be saved about 5 to 7.8 %. Finally, the optimal operation efficiency of indirect evaporative condenser used in this study is obtained when the system’s condensation pressure is working at 1280 kPa.

並列關鍵字

Indirect Evaporative Condensers ； Evaporative Section ； Fin-and-tube heat exchangers

參考文獻

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[1] http://www.gov.tw/PUBLIC/view.php3?id=81831&sub=52&main=GOVNEWS.