冷卻水塔熱性能之數據計算分析與實驗驗證

The Comparison of Numerical Data with Experimental Results Data of the Thermal Performance for Induced Cooling Tower

羅金枝(Chin-Chih Lo)

指導教授 ： 張永鵬

中原大學/工學院/機械工程研究所/碩士(2006年)

https://doi.org/10.6840/cycu200600043

摘要

中文摘要
冷卻水塔熱質傳數學模型的建構，係以Merkel是所提之焓位勢理論為基礎，發展成冷卻水塔效能的計算模式，其中焓位勢之積分式是無法用解析解而得，雖然數值方法發展很早，終究人腦不擅於複雜的計算，有賴於近年來電腦計算能力急速提昇，數值方法運用於計算冷卻水塔更趨普遍。本文就C.T.I.習用之修正係數屈伯希夫法及辛普森法對於冷卻水塔之熱效能計算結果作ㄧ差異比較，研究得知於計算冷卻水塔效能時，於溫差超過15℃以上時，C.T.I.習用之修正係數屈伯希夫法有比辛普森法差異較大的趨勢，這是由於假設條件是出口空氣是飽和。但在冷卻水塔用於較高溫差條件時，出口空氣往往未達飽和，就已被導引風機所帶走，是造成差異的條件之ㄧ。且使用辛普森法比較易懂，容易使用，這是許多人建議使用此法之處。

關鍵字

冷卻水塔

並列摘要

Abstract
To establish the mass transfer mathematical model of the cooling tower thermal efficient calculation, this is based on the enthalpy potential theory. The enthalpy potential theory is powerful used in cooling tower thermal efficient calculation, which is suggested by Merkel’s. The integral formula of the enthalpy potential can’t obtain by analytical solution. The numerical analysis is developed long time ago, but their calculation proceed is very complexity. Recently, the computer calculation ability had fast developed, so their application is very popular, for example, what the cooling tower thermal efficient calculation.
The correction coefficient calculation of the cooling tower thermal efficient is almost used Chebyshev’s method and Simpson’s method, the former is suggested by C.T.I. In this study, we had made a compare for this two methods and find when the approach temperature (inlet cooling water temperature subtract inlet air wet bulb temperature) over 15 ℃, the calculation result of the cooling tower thermal efficient which obtained by Chebyshev’s method will be more than the Simpson’s method. Due to the outlet air temperature is almost assume at saturate condition, but, the more approach temperature, the outlet air temperature more deviated saturate condition (the outlet air had not reach to saturate condition when they departed cooling tower). This is the reason why the calculation result which is by the prerequisite methods will be caused a differential phenomenon.
In the past, the Simpson’s method is comparatively easy to understand and put to use, so this method is a universal method for cooling tower industry.

並列關鍵字

cooling tower

參考文獻

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