可用能分析應用於水冷式箱型冷氣機能源效率診斷之研究

Exergy Analysis for Energy Efficiency Diagnosis of Package Air Conditioner

郭榮崇(Jung-Chung Kuo)

指導教授 ： 李宗興

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2006年)

摘要

水冷式箱型冷氣機是直膨蒸氣壓縮冷凍系統，應用在商業與工業領域中之空氣調節設備。箱型冷氣機之性能的評量通常是採用能源效率比 (energy efficiency ratio, EER) 在CNS-3615中有規定，然而這些性能指標均是利用熱力學第一定律觀點所建立的，只能來代表冷凍系統整體效率。對於箱型冷氣機開發過程中，為達到CNS-3615所規定能源效率比的要求，經常去更改各元件的設計，但只能瞭解冷凍系統整體效率，卻無法進一步去瞭解改善各元件對於能源效率的提升效益，並且提供明確的方向，應從何元件著手。
因此本文之主要研究目的為：藉由熱力可用能分析，發展可供應用於分析水冷式箱型冷氣機系統與元件能源效率之可用能分析模式，並探討控制容積選取與邊界熱傳溫度對於元件可用能毀滅(exergy destruction)、可用能效率(exergy efficiency)及其比重排序的影響。最後，利用三組實驗案例之驗證來確認所建立模式的適用性，藉由可用能分析作為診斷水冷式箱型冷氣機系統與元件能源效率改善成效之可行性。研究結果顯示：在實務上水冷式箱型冷氣機可利用Model-3可用能分析，控制容積的範圍要包含元件冷媒側、空氣側與冷卻水側，邊界溫度直接採用環境溫度To來進行分析較為方便。所有實驗案例均顯示各主要元件的可用能毀滅最大為蒸發器，其次為壓縮機，第三為冷凝器，最後為膨脹裝置；各主要元件的可用能效率最小為蒸發器，其次為壓縮機，第三為冷凝器，最後為膨脹裝置。本文所獲得的結論將可提供水冷式箱型冷氣機設計開發者對於系統的能源效率改善之診斷工具，應從可用能毀滅最大、可用能效率最小的元件著手改善。

關鍵字

可用能毀滅 ； 可用能效率 ； 不可逆性 ； 箱型冷氣機

並列摘要

Water-Cooled type air-conditioner is direct expansion vapor compression refrigeration system and application to air-conditioning equipment in industry and commerce. According to CNS-3615, the air-conditioner performance's usually express energy efficiency ratio (energy efficiency ratio, EER). But the performance indicator utilizes the first law of thermodynamics to establish, and it can represent whole efficiency of the refrigeration system. Towards package air conditioner development process in, the energy efficiency ratio must be to obey CNS-3615, so designers often go to change component’s design, but can only know refrigerating system whole efficiency, unable to go to understand and improve increasing the benefit to energy efficiency of component, and offer the clear direction, where the component is set about.
Therefore the main research purposes of this study is developing an exergy analysis mode for system component’s energy efficiency of Water-Cooled Package Air Conditioner. The control volume and boundary temperature will be discuss exergy destruction, exergy efficiency and its proportion affection. Final, use three groups of experience case verify to establish mode's applicability, bring up by means of by exergy analysis as consultation Water-Cooled Air-Conditioner system component energy efficiency ameliorate effect feasibility. The results show : Water-Cooled type air-conditioner can use Model-3 exergy analysis and control volume contains element, refrigerating side, air side, and cooling water side. The boundary temperature directly adopt environmental temperature is more convenience to analyze. All experience case show the evaporator’s exergy destruction will be the biggest, secondly is compressor, thirdly is condenser, finally is expansion device; The evaporator’s exergy efficiency is the smallest, secondly is compressor, thirdly is condenser, finally is expansion device.
This study conclusion will supply Water-Cooled type air-conditioner designer and developer towards to promote energy efficiency and to do ameliorate diagnostic tool that should to improve component’s energy efficiency from exergy destruction is the biggest and exergy efficiency lowest.

並列關鍵字

exergy destruction ； exergy efficiency ； irreversibility ； package air conditioner

參考文獻

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