R-134a應用於雙蒸發器冷凍系統之效能研究

Performance of a parallel two-evaporatorRefrigerator with R-134a

黃鴻河(Hung-He Huang)

指導教授 ： 李文興

國立臺北科技大學/機電學院/冷凍空調工程系所/碩士(2005年)

摘要

過去的冷氣機、冰箱、及各式小型空調等大多以R-22冷媒做為工作流體，基於環保概念，因R-22冷媒具有較高的臭氧破壞潛能(ODP) ，且從HCFC冷媒亦於2030年後禁止使用，將以R-134a冷媒取代R-22在雙蒸發器冷凍空調系統作討論。
本研究R-134a冷媒其運用於雙蒸發器時高低壓段膨脹閥開口度及降壓閥調節瞭解其蒸發特性及性能探討。實驗系統由渦卷式壓縮機、兩個蒸發器、一各冷凝器及兩個手動是膨脹罰、一個降壓閥組成，並搭配變頻器進行性能實驗。
研究後發現膨脹閥開口度、降壓閥與壓縮機頻率之變化對系統的性能有著很大的影響，當高壓蒸發器固定開口度、低壓蒸發器開口改變其蒸發溫度將隨之上升，當降壓閥的開度改變，高低壓蒸發器的蒸發溫度也隨之改變為不同之蒸發壓力。

關鍵字

雙蒸發器 ； 膨脹閥 ； R-134a ； 降壓閥 ； 變頻

並列摘要

In the past, all sizes of air handling units applied freon R-22 as the working fluid where due to environmental awareness that the freon R-22 creates higher ODP, so HCFC will be banned forever for use and freon R-22 will be replaced by R-134A for good. This study use experimental method investigate the performance on a R-134a dual evaporator refrigerator system. The study reveals the fact that the openness of the expansion valve, the frequency change in pressure reduction valve and compressor render significant effect on the performance of the system; When the high pressure steam evaporator is set at a fixed openness, the openness of the low pressure evaporator will raise the steam temperature. When the openness of the pressure reduction valve is changed, the steam temperature of the high and low pressure evaporators change in line with the steam pressure. Contrarily, when the low pressure evaporator is set at a fixed openness, the changing openness of the high pressure evaporator will come out the same result. This study is to get familiarized with performance features of the application of R-134A on the dual evaporator when the openness of the high and low pressure expansion valves are regulated accordingly.

並列關鍵字

Dual Evaporator ； Expansion Valve ； R-134a ； Pressure Reduction Valve Frequency Conversion

參考文獻

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