臺灣博碩士論文加值系統

本文研究大型管冷型馬達的殼管式熱交換器冷卻管排列以減少冷卻管的使用數量，我們固定熱交換器的入口流速，改變冷卻管的數量以及排列位置，討論五種冷卻管的排列方法。
方法一，在空腔時找尋速度場最快位置增加冷卻管。方法二，在擺滿冷卻管時移除最差熱傳率的冷卻管。方法三，橫排區域增加冷卻管。方法四，依據方法一，在空腔時的速度快慢順序增加冷卻管；以及依據方法二，在擺滿冷卻管時的熱傳率大小順序移除冷卻管。方法五，對稱英文字母排列。我們比較在五種方法的冷卻管排列下，對於殼管式熱交換器的散熱效率之影響，找尋最佳的冷卻管排列方法，有助於熱交換器的設計與開發。
在研究中發現方法一、二、三的冷卻管數量對應熱傳率效率的曲線都極為相似，而且也是這五種方法中最好的，其中方法三的模擬分析的過程是最簡單的，因此我們認為最終的方法是方法三，使用135根冷卻管，熱傳率效率為82%；以及使用180根冷卻管，熱傳率效率89%，其冷卻管數量分別減少了57%以及42%。

In this thesis, we studied cooling tube arrangements of the shell-and-tube heat exchanger used in large motors. The objective is to minimize the number of the cooling tube used in the heat exchanger when the heat exchange performance is specified. We fix the inlet velocities of the heat exchanger and vary the cooling tube number and their locations. There are five schemes of arranging cooling tubes proposed in this study.
Scheme A: Placing cooling tubes according to the velocity field of the shell part. Cooling tubes are placed to the highest velocity locations. Scheme B: Removing cooling tubes according to their heat transfer rate. Cooling tubes with the lowest heat transfer rate will be removed first. Scheme C: Adding cooling tubes row by row. Scheme D-1: The velocity distribution of a empty shell part is sorted. Cooling tubes are placed according to the sorting. Scheme D-2: The heat transfer rates of the cooling tube part is sorted. Cooling tubes are removed according to the sorting. Scheme E: Cooling tubes are placed in "O", "X", and "M" shapes. We compared these five schemes in their influences on the shell-and-tube heat exchanger's performance. The optimal scheme for arranging cooling tubes is desired.
The results show that Schemes A-C are the best among five schemes. Using these three schemes, cooling tube arrangements have similar heat exchange performances. However, Scheme C is the easiest to apply among these three schemes. When Scheme C is used, to maintain a heat transfer performance of 82% and 89% will require a usage of 135 and 180 cooling tubes, respectively. The reduction in cooling tube usage is 57% for 135 cooling tubes and 42% for 180 cooling tubes.

致謝I
摘要II
Abstract III
目錄IV
圖目錄VII
表目錄IX
符號說明X
第一章 緒論1
1.1 前言1
1.2 低極數(2P-8P)大型管冷型馬達介紹1
1.3 熱交換器工作原理與種類2
1.4 研究動機與目的4
1.5 文獻回顧5
1.5.1冷卻管設計文獻5
1.5.2擋板設計文獻8
1.5.3其他應用文獻11
1.6 本文架構14
第二章 理論模型建立與設定15
2.1 紊流(Turbulent Flow)模型方程式17
2.2 模型建立19
2.3 網格測試24
2.4 邊界條件設定25
2.4.1冷端流場入口邊界設定28
2.4.2冷端流場出口邊界設定28
2.4.3熱端流場入口邊界設定29
2.4.4熱端流場出口邊界設定29
2.4.5冷端及熱端流場共用面設定30
2.5 求解器設定以及收斂條件30
2.5.1求解器設定30
2.5.2收斂條件31
第三章 研究方法與模擬結果討論32
3.1 在空腔時找尋速度場最快位置增加冷卻管35
3.1.1研究方法35
3.1.2模擬結果39
3.2 在擺滿冷卻管時移除最差熱傳率的冷卻管46
3.2.1研究方法46
3.2.2模擬結果46
3.3 橫排區域增加冷卻管55
3.3.1研究方法55
3.3.2模擬結果55
3.4 依據章節3.1的速度快慢以及章節3.2的熱傳率大小排列63
3.4.1研究方法63
3.4.2模擬結果63
3.5 對稱英文字母排列69
3.5.1研究方法69
3.5.2模擬結果69
第四章 結論與未來展望79
4.1 結論79
4.2 未來展望80
參考文獻82

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