系統識別號 | U0002-1108201514451900 |
---|---|
DOI | 10.6846/TKU.2015.00278 |
論文名稱(中文) | 異重流於下坡加速運動之高解析度模擬 |
論文名稱(英文) | High-resolution simulation of downslope gravity currents in the acceleration phase |
第三語言論文名稱 | |
校院名稱 | 淡江大學 |
系所名稱(中文) | 水資源及環境工程學系碩士班 |
系所名稱(英文) | Department of Water Resources and Environmental Engineering |
外國學位學校名稱 | |
外國學位學院名稱 | |
外國學位研究所名稱 | |
學年度 | 103 |
學期 | 2 |
出版年 | 104 |
研究生(中文) | 黃友麟 |
研究生(英文) | Yu-Lin Huang |
學號 | 602480187 |
學位類別 | 碩士 |
語言別 | 繁體中文 |
第二語言別 | |
口試日期 | 2015-06-16 |
論文頁數 | 36頁 |
口試委員 |
指導教授
-
許中杰
委員 - 盧博堅 委員 - 戴璽恆 |
關鍵字(中) |
異重流 密度流 浮力 |
關鍵字(英) |
gravity currents density currents buoyancy |
第三語言關鍵字 | |
學科別分類 | |
中文摘要 |
本研究為數值模擬二維性異重流於不同角度下加速段之流況,並且在Boussinesq假設下,以數值方法解不可壓縮的 Navier-Stokes 方程式。在不受到實驗條件限制的情況下,能夠自由選取斜板角度0°≤θ≤90°,也能控制其它變因並且比較其中差異,如:雷諾數、水深比。在先前研究中Beghin et al.(1981),他們無法準確找出最大的速度U_(f,max)發生的角度,透過數值運算,我們能準確分析在θ=40°的時候,U_(f,max)最大值會在此發生。 |
英文摘要 |
This paper is a two-dimensional numerical simulation of gravity current in the acceleration phase at different angles, and the problem have been solved by numerical methods of the incompressible Navier-Stokes equation with the Boussinesq approximation. Without the limited of experimental condition, can freely selected the plate angle 0°≤θ≤90°, and control other factor (Reynolds number, depth ratio) which can compare the difference. In a previous study (Beghin et al 1981), they can not accurately indentify the maximum U_(f,max) occurs angle. Though numerical computation, we can accurately find when θ=40° , the maximum U_(f,max) will occur in this. |
第三語言摘要 | |
論文目次 |
目錄 表目錄 V 圖目錄 VI 第一章 緒論 1 1-1 前言 1 1-2 動機與目的 2 1-3 文獻回顧 3 第二章 理論分析 4 2-1 熱理論 4 第三章 研究方法 7 3-1 數值方法 7 第四章 結果分析 11 4-1 概況 11 4-2 角度影響 15 4-3 混合區域 18 4-4 能量預算 20 4-5 水深比影響 24 4-6 雷諾數影響 27 4-7 頭部重力比例 29 第五章 結論 32 5-1 總結 32 參考文獻 34 表目錄 表 1 二維模擬在不同章節所需參數表 10 圖目錄 圖 1 異重流在斜坡傳播示意圖 4 圖 2 異重流在角度9°,Re = 4000流動圖 11 圖 3 2013 A.Dai 在實驗圖 12 圖 4異重流在不同角度下∅=0.16,Re=4000,無因次速度與時間關係圖 13 圖 5不同角度下達最大前頭速度Uf,max流動示意圖 14 圖 6 (a)無因次Uf,max與不同角度關係圖(b)無因次加速時間tc關係圖 15 圖 7異重流θ=2°,Re=4000流動示意圖 17 圖 8異重流在不同角度下,無因次混合面積與時間關係圖 18 圖 9經標準化後,總能,動能,損失隨時間變化圖 22 圖 10異重流在不同水深比下,前頭速度與時間關係圖 24 圖 11水深比∅= 1,0.16經標準化後,總能,動能,損失隨時間變化圖 25 圖 12異重流在不同雷諾數下,t = 4.42密度散布圖 27 圖 13最大前頭速度Uf,max與不同雷諾數的關係圖 28 圖 14異重流在θ=9°,加速時間 tc =7.78,∅ = 0.16,Re = 4000,密度分部圖 29 圖 15異重流頭部重力與全部重力的比值BHB0 ,和判別值ρc關係圖 30 圖 16頭部重力與總重力比值BHB0,與角度關係圖 31 |
參考文獻 |
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