提升氣冷式冰水機性能之參數分析

Parameter Analysis for Improving Performance of Air-Cooled Liquid Chillers

張智翔(Chich-Hsiang Chang)

指導教授 ： 李宗興

國立臺北科技大學/機電學院/能源與冷凍空調工程系碩士班/碩士(2007年)

摘要

氣冷式冰水機一般廣泛使用在工業以及商業都市大樓，並且為主要耗能設備之一。而經濟部能源局針對氣冷式冰水機性能係數(COP)要求之公告標準值為2.79，和EU視為A級之3.1則有11%差距，至於和CAS之A級3.4則有22%差距。因此，探討國內氣冷式冰水機性能效率之提升空間，為本文主要研究目的。本文藉由發展各元件熱力模式，針對氣冷式冰水機進行性能模擬；並透過不同參數組合，探討氣冷式冰水機性能效率之提升空間與系統各元件能源轉換效率之情形。考量之設計參數有: 冷凝盤管夾角配置、壓縮機效率以及蒸發器型式進行分析。研究結果發現：
三種改善方式以壓縮機等熵效率對於系統整體性能以及總不可逆性影響最大，其次為蒸發器型式，最後為盤管夾角配置。若採用壓縮機等熵效率為0.7、盤管配置為Type A、B、C以及採用滿液式蒸發器接可以達到歐盟A級之性能標準。但若要達到中國國家標準(CAS)所規定之A級標準3.4，在實務上可能達到範圍下，則沒有任何一種配置可能達到CAS之A級規範。

關鍵字

氣冷式冰水機 ； 參數分析 ； 可用能分析

並列摘要

Air-cooled chiller has been widely used in industrial and commercial buildings. It is the major electricity consumption machines of the building. The Bureau of Energy suggestion coefficient of performance (COP) for air-cooled chiller is 2.79. It is difference in COP between Bureau of Energy 2.79 and regarded as A grade with EU standard 3.1, the disparity is 11%. It is compared with CAS standard 3.4 have 22% disparity. Therefore, the objective of this study is how to improve COP of air-cooled chiller. For this reason, this paper develops thermodynamic model of the components to evaluate COP of an air-cooled chiller. This paper have take account of the different parameters to effect on COP of air-cooled chiller and use exergy analysis to discuss energy transfer efficiency of the components of air-cooled chiller. In this paper, the parameters below are in considerations: coil configuration of condenser, evaporator type and isentropic efficiency of compressor to analysis. The results show that:
The most influential of system performance is isentropic efficiency of compressor, followed evaporator type and then coil configuration of condenser. If used 0.7 isentropic efficiency of compressor, type A, B and C coil configuration of condenser and flooded evaporator. It can reach the COP standard of European Union's A grade. But if will reach China's standard (CAS) 3.4, under the possible reach on the practice, there is no any kind of disposition may reach.

並列關鍵字

air-cooled chiller ； parameter analysis ； exergy analysis

參考文獻

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