氣冷式冰水機冷凝盤管配置之實驗量測與分析

Experimental Investigation for Optimum Configuration of Air-Cooled Condensing Coils

王志維(Chih-Wei Wang)

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(2006年)

摘要

大型氣冷式冰水機的冷凝器通常係由多組鰭管式冷凝盤管所組成，由於受到機組外型尺寸限制，使得冷凝盤管配置有多種設計考量。然而，冷凝盤管配置得當與否會明顯影響通過盤管氣流分佈的均勻性，連帶影響冷凝盤管散熱能力。此外，盤管底部元件與配電盤之擺設方式、風機轉速的改變、以及導流板設置方式，都會影響盤管速度分佈均勻性。為了改善冷凝盤管表面速度分佈與提高熱傳性能，尋找最佳冷凝盤管配置的研究便成為提升此類設備性能的重要課題。因此，本文主要研究目的在於: 在相同機組外型尺寸與風機性能等條件之前提下，利用實驗量測與分析的方式，探討冷凝盤管配置夾角、底部元件擺設高度、加裝導流板、控制盤擺設位置、以及改變風機轉速等因素，對於通過冷凝盤管速度分佈之影響，藉以找出最佳配置方式。此外，亦藉助於熱傳分析模式，計算與評估各案例之熱傳性能改善效益。研究結果發現：冷凝盤管夾角改變，可使平均風速提高2.7%，熱傳量可提高2.0%；底部元件擺設高度對通過冷凝盤管速度分佈均勻性的影響極大，內外側盤管平均速度差異甚至高達約兩倍；加裝導流板，最佳案例可提高平均速度達4.6%，熱傳量則為3.4%；配電盤擺設位置對平均速度與熱傳量的影響，則分別為2.8%與2.0%；提高風機轉速，平均速度亦隨之上升。

關鍵字

氣冷式冰水機 ； 冷凝盤管 ； 鰭管式熱交換器

並列摘要

The condenser are compose of many finned-tubes condensing coil for air-cooled liquid chiller. Because of the chiller size is fixed, for this reason it have different configurations of condensing coil. The configuration of condensing coil will strong affect pass condensing coil of velocity distribution, and affect condensing coil heat rejection capacity. It could be affect coil of velocity distribution, When change the under component、guide plate、switchboard configuration, and fan speed. Therefore, how to find out the optimum configuration to improve condensing coil face velocity distribution and to raise heat transfer performance, it will be the main target for performance promotion of air-cooled liquid chiller. The main purpose of this study is to find out the optimum of configuration by experimental measurement and analysis of condensing coil velocity distribution in all case under the same chiller size and fan performance. Moreover, it using heat transfer analysis model computation and estimation heat transfer performance improve benefit in all cases.
The results show that: When change condensing coil configuration the average velocity could raise 2.7% and the heat transfer could raise 2.0%. The under components height will strong affect pass condensing coil velocity distribution uniform, inside and outside coil average velocity difference about two times. The optimum case of guide plate the average velocity could raise 4.6% and the heat transfer could raise 3.4%. The optimum case of switchboard the average velocity could raise 2.8% and the heat transfer could raise 2.0%. It raise to fan speed the average velocity it will be raise.

並列關鍵字

Air-cooled liquid chiller ； condensing coils ； finned-tubes heat exchanger

參考文獻

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