中 文 摘 要

本文以數值分析法研究太陽能儲水槽於右側壁面為定負載下的自然對流現象，統御方程式化為渦度-流線方程式求解。數值解法為高斯-塞德(Gauss-Seidel)有限差分法(finite-difference method)隱式結構(implicit scheme)。探討參數有:瑞里數(Ra)、熱管長(L)、熱管厚(d)、熱管與儲水槽底部壁面距離(h)、以及熱管與儲水槽夾角( )等五個參數，在容器展弦比(AR)為1的對流熱傳現象。計算結果為熱傳效果隨著瑞里數、熱管長、熱管厚、以及夾角的增加而增加，加熱區以位於水槽底部時熱傳效果最好。

ABSTRACT

The natural convection phenomenon in solar energy water trough for stable loading on a wall is studied numerically in this paper. Governing equations are transformed in vorticity-stream equations. Gauss-Seidel method with finite-difference implicit scheme was applied. The effects of the parameters of Rayleigh number, heat pipe length, heat pipe thickness, the distance from heat pipe to down side of water trough and the studied angle of inclination. The results indicate that the heat transfer coefficients increase with the Rayleigh number, the heat pipe length, the heat pipe thickness and the angle of inclination.

目 錄

摘要(中)…………………………………….……….…… I
摘要(英)…………………………………….……….…… II
目錄......…......................………………………...….…. Ⅲ
圖目錄............................…………………..………...… Ⅴ
符號說明...........................………………………..……. Ⅸ
程式變數列表....................………………………..……. ⅩⅠ


第一章 緒論...............…………………………........... 1
1-1 前言..........………………………………............ 1
1-2 文獻回顧…………………………………….…… 3
1-3 本文結構…………………………………………. 4

第二章 理論分析.....……………………………........... 5
2-1 基本假設....………………………………............ 5
2-1 數學模式...………………………………............ 5
2-2.1 統御方程式………………………………… 5
2-2.2 無因次化…………………………………… 8
2-2.3 邊界條件…………………………………… 12
2-2.4 熱通量、熱係流係數、紐塞爾數……….. 12

第三章 數值方法與說明……………...........……………... 14
3-1 序…….....………………………………........... 14
3-2 格點配置....………………………………........... 14
3-3 數值解析....………………………………........... 14
3-4 求解程序....………………………………........... 18

第四章 結果與討論……………...........…………..……... 19
4-1 溫度場及流場的討論……………………........... 20
4-1.1 瑞里數…….………………………….…… 20
4-1.2 熱傳面積…………………………………… 22
4-1.3 加熱區域位置……………………………… 23
4-1.4 熱管與儲水槽夾角………………………… 24
4-2 結論………………..……………………........... 25
4-3 建議………………..……………………........... 26

參考文獻....……………………………….…………....… 66

程式…......……………………………….…………....… 69

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