小型並聯式雙蒸發器冰水主機性能分析

Performance Analysis of a Parallel Two-Evaporator Refrigerator

陳泳棋(Yun Chi Chen)

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(2006年)

摘要

本文建立了基本分佈參數及雙蒸發器的熱力學模型，對並聯式雙蒸發器系統穩態特性及分佈元件間耦合關係進行數值模擬研究，為雙蒸發器的優化設計，控制方法提供相關依據。
研究後發現在低溫蒸發器溫度固定下，冰水負載及冷卻水負載不變下，提升壓縮機頻率由30HZ上升至60HZ時，系統整體COP值由5.3降至3.75，整體壓縮效率下降，而此可以知道雙蒸發器之變頻節能，控制在特定的頻率下效果會更加良好，而研究後也發現當調節冷卻水溫度上升時，低溫蒸發溫度固定下，冰水負載通入溫度不變下，當冷卻水溫度上升10C時，整體COP下將約為0.15；而低溫蒸發溫度的改變，對整體系統之效能也有所影響。

關鍵字

雙蒸發器、R-134a、冷凍空調、變頻

並列摘要

This study uses theoretical method to investigate the performance of a two-evaporator refrigerator. The theoretical model is established based on thermodynamic and fluid theory. A simulation program is set up on one dimension steady state.
The result show that on operated condition, constant evaporator temperature of lower-temperature evaporator, COP drops from 5.3 to 3.75 as the compressor frequency increase from 30Hz to 60Hz and COP decrease 0.15 as inlet cooling water increase 1℃.

並列關鍵字

two-evaporator、R-134a、air condition and refrigeration、Frequency conversion

參考文獻

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