臺灣博碩士論文加值系統

本論文係對一公稱5冷凍噸之系統進行實機測試，依據中國國家標準進行冷房及暖房運轉之實驗。在實驗過程中，記錄標準條件及結霜過程之暖房能力及性能係數（COP）的變化。文中亦特別探討系統在除霜過程中之動態變化。
研究之測試條件涵蓋—4℃ 至 7℃之室外環境溫度及60％至90％之相對濕度。研究結果提供了暖房模式運轉在結霜及除霜過程中之詳細特性。
實驗結果顯示，在控制策略上，除霜過程中需使低壓保護開關短暫失效，系統才能正常連續運轉。當室外環境溫度降至-4℃時，暖房平均加熱能力為額定加熱能力之62%，而暖房平均性能係數COPh為額定值之71%。入口空氣乾球溫度1.5℃時，相對濕度較高之條件，在暖房模式運轉初期，暖房能力及性能係數COPh高於入口空氣相對濕度較低之運轉條件;但隨運轉時間之增加，霜層亦增加較快，變成熱阻後，暖房能力及性能係數COPh便大幅降低。相對濕度較低之條件，霜層增加較慢，亦延長了除霜間隔時間。

An air-to-water heat pump of nominal 5-ton capacity was instrumented and tested in the heating mode under laboratory conditions. The coefficient of performance (COP) and heating capacity of the system were measured during standard and frosting/defrosting conditions, with major emphasis placed on the dynamic frosting operation of the system.
The study encompassed an evaluation of system performance for ambient temperature levels between -4℃ and 7℃ and for discrete relative humidity levels ranging from 60% to 90%. A detailed description of the physical processes that occur during defrost is provided.
The results indicate that low-pressure cutout needs to be overridden during defrosting thus system could run continually without trip. At an ambient temperature of -4℃, the average heating capacity was 71% of the nominal value and the average coefficient of performance was 62% of the nominal COP. With a —1.5℃ ambient air temperature, system COP and capacity improved slightly under condition of higher humidity in the non-frosting period. The frost accumulation on the outdoor heat exchanger increased the resistance thus reduced both system COP and capacity. Ice formation increased more slowly with lower humidity. It results an extended defrost interval.

中文摘要
英文摘要
誌謝
目錄
表目錄
圖目錄
符號說明
一.緒論
1.1前言
1.2研究動機與研究目的
1.3文獻探討
1.4名詞定義
二.系統描述
2.1熱泵原理敘述
2.1.1熱泵原理
2.1.2熱泵循環
2.1.3熱泵效率
2.2氣冷式冰水熱泵系統
2.2.1壓縮機
2.2.2空氣冷卻鰭管式熱交換器
2.2.3板式熱交換器
2.2.4感溫式膨脹閥
2.2.5四方閥及逆止閥
2.2.6控制系統
2.3冷房及暖房操作流程
2.4除霜控制
三.理論分析
3.1冷暖房模式之性能分析
3.2熱交換器熱傳分析
3.3壓力比對暖房運轉之影響
3.4加熱容量與加熱負載之平衡點
四.實驗設備與方法
4.1實驗設備
4.2實驗條件
4.3實驗方法
五.實驗結果與討論
5.1冷房測試:乾球溫度35℃,濕球溫度24℃
5.2暖房測試
5.2.1 乾球溫度7℃,濕球溫度6℃
5.2.2 乾球溫度1.5℃,濕球溫度0.5℃
5.2.3 乾球溫度-4℃,濕球溫度-5℃
5.2.4 乾球溫度1.5℃,不同相對濕度之實驗分析
六.結論
七.建議
參考文獻

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