臺灣博碩士論文加值系統

摘要
本篇採用熱力第二定律探討在一緩慢的飽和蒸汽由上往下緩慢流經表面具等熱通量之圓管，而產生凝結的熵增分析。本研究結合對流熱傳下熵增原理與膜狀凝結熱傳研究方法，針對不同的Brinkman、Rayleigh、Peclet參數等效應與不可逆率無因次參數探討。結果發現局部熵增隨Brinkman數增加而變大。當Rayleigh數遞增時，無因次熱傳參數增強，然而也造成局部熵增率增加。熱傳不可逆率主導整個熵增系統。另外本文也加入壁吸效應，將結果與無壁吸效應做比較。

關鍵詞：熵、等熱通量、膜狀凝結、圓管、壁吸流

Abstract
This paper uses thermodynamic second law to perform entropy generation analysis for saturated vapor flowing slowly onto and being condensed on a horizontal tube with uniform wall heat flux. Based on entropy generation theory and film condensation heat transfer analysis, the effects of various parameters as Brinkman number, Rayleigh number, Peclet number and irreversibility ratio on local entropy generation rate are investigated The result shows that local entropy generation rate increases with Brinkman group parameters. As Rayleigh group parameters increase, dimensionless heat transfer coefficient is enhanced, but entropy generation number is augmented too. The heat transfer irreversibility dominates the system of entropy generation. In addition condition of flow suction at the porous wall is also studied and compared with that of no suction effect .
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Keywords: Entropy, Uniform wall heat flux, Film condensation, Tube,suction

目錄
中文摘要
英文摘要
誌謝
目錄
圖目錄
符號說明
第一章 前言
1-1熱力學之基本定律
1-2 熵的定義
1-3 凝結物理模式
1-4 文獻回顧
1-5 論文結構
第二章 物理模式及基本定義分析
2-1對流熱傳之局部熵增變化
2-2 流動摩擦不可逆率與熱傳不可逆率
第三章等熱通量水平圓管膜狀凝結之熵增分析
3-1物理模型與理論分析
3-2 結果與討論
3-2-1 水平圓管管外流膜狀凝結之局部熵增變化
3-2-2 水平圓管管外流膜狀凝結之平均熵增變化
第四章 具均勻壁吸效應之水平圓管等熱通量膜狀凝結之熵增分析
4-1 物理模式與理論分析
4-2結果與討論
4-2-1具壁吸效應下之水平圓管等熱通量膜狀凝結之局部熵分析
4-2-2具壁吸效應下之水平圓管等熱通量膜狀凝結之平均熵分析
第五章 結論
5-1 綜合討論
5-1-1 無壁吸流效應情形下，局部與總體熵增方面：
5-1-2 具均勻壁吸流效應情形下，局部與總體熵增方面：
5-1-3共同類似結論
5-2 未來研究方向與建議
參考文獻
簡歷

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