系統識別號 | U0002-1408200805351400 |
---|---|
DOI | 10.6846/TKU.2008.00368 |
論文名稱(中文) | 氫氣合成填充式反應器之計算流體力學研究 |
論文名稱(英文) | CFD study on packed bed reactors for hydrogen synthesis |
第三語言論文名稱 | |
校院名稱 | 淡江大學 |
系所名稱(中文) | 化學工程與材料工程學系碩士班 |
系所名稱(英文) | Department of Chemical and Materials 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 | 96 |
學期 | 2 |
出版年 | 97 |
研究生(中文) | 凃芳平 |
研究生(英文) | Fang-Ping Tu |
學號 | 695401553 |
學位類別 | 碩士 |
語言別 | 繁體中文 |
第二語言別 | |
口試日期 | 2008-07-25 |
論文頁數 | 151頁 |
口試委員 |
指導教授
-
張煖(nhchang@mail.tku.edu.tw)
委員 - 尹庚鳴(cekenyin@saturn.yzu.edu.tw) 委員 - 陳錫仁(hjchen@mail.tku.edu.tw) |
關鍵字(中) |
計算流體力學模擬 填充床反應器 觸媒反應器 氫氣 紊流 |
關鍵字(英) |
Computational Fluid Dynamics Packed Bed Reactor Catalytic Reactor Hydrogen Turbulent Flow |
第三語言關鍵字 | |
學科別分類 | |
中文摘要 |
本論文使用計算流體力學(Computational Fluid Dynamics,CFD) 軟體FLUENT配合一系列之使用者自定函數(User Defined Function, UDF)完成了自甲烷的自熱重組反應(ATR, Autothermal Reforming)生成氫氣之填充床式觸媒反應器(Packed Bed Catalytic Reactor,PBR)之三維模式模擬,模式納入了填充床球型觸媒顆粒反應器中(1)巨相之流力、熱傳與質傳;(2)觸媒顆粒內之流力、熱傳、質傳與化學反應;(3)巨相與觸媒顆粒間之流力、熱傳與質傳。 透過模擬探討了反應器內部之特性分佈,包括壓力、速度、溫度與組成,並探討了參數之影響,包括觸媒球表面處理、雷諾數、孔徑、觸媒球粒徑、不同進氣條件等。針對填充床之摩擦因子以及觸媒顆粒與巨氣相間之熱傳係數與質傳係數,本研究並比較模擬結果與文獻關聯式,結果顯示摩擦因子與Durst等人修正之Ergun方程式較吻合,熱傳係數與質傳係數則分佈零散,並未呈現特別與某一關聯式較吻合之情形。 |
英文摘要 |
This thesis uses Computational Fluid Dynamics, combining with a set of User Defined Functions (UDF) to accomplish the simulation studies for the Packed Bed Catalytic Reactor (PBR) for hydrogen generation from steam reforming of methanol. The model encompasses all important mechanisms for PBR, including (1) the hydraulic, heat and mass transfers of bulk gas; (2) the hydraulic, heat and mass transfers and chemical reaction of catalyst; (3) the hydraulic, heat and mass transfers between bulk gas and catalyst. The simulation is for turbulent flow regime. The simulation facilitates the discussions on the profiles inside the reactor, including pressure, velocity, temperature and composition. The effects of catalyst particle pore size, catalyst particle diameter, fluid inlet velocity and the location in the reactor are studied. The ways of treating catalyst particle surface friction are investigated too. The friction factor of the bed and the heat and mass transfer coefficients between catalyst particle and bulk gas are compared with the correlations reported in the literature. The friction factor vs. Reynolds number relation is close to the Durst et al. modified Ergun equation, while Nusselt number vs. Reynolds number and Sherwood number vs. Reynolds number relations are scattered distributed and cannot be described well by reported correlations. |
第三語言摘要 | |
論文目次 |
致謝……………………………………………………………………………………..i 中文摘要………………………………………………………………………………iii 英文摘要………………………………………………………………………………iv 目錄 v 圖目錄 vii 表目錄 xii 第一章 前言 1 第二章 文獻回顧 3 2.1 填充床式反應器 3 2.2 氫氣生成反應系統 4 第三章 氫氣生成系統 6 3.1化學反應和反應動力 6 第四章 計算流體力學模式之建立 9 4.1系統配置與網格建立 9 4.2 數學模式 13 4.2.1基本統制方程式 13 4.2.2 紊流模式 13 4.2.3 邊界條件 16 4.3 附加程式與設定 18 4.3.1 自訂函數 18 4.3.2 離散方法 21 4.3.3 迭代運算控制參數 22 4.3.4 收斂準則 23 第五章 個案模擬結果 24 5.1 模擬個案總說明 27 5.1.1 個案之設定條件 27 5.1.2反應程度 28 5.1.3有效因子 29 5.1.4 質傳通量 32 5.2 基本個案內部分佈 39 5.2.1 壓力分佈 39 5.2.2 速度分佈 44 5.2.3 溫度分佈 48 5.2.4 組成分佈 53 5.3 個案比較 78 5.3.1 觸媒顆粒表面條件之影響 78 5.3.2 雷諾數之影響 87 5.3.3 孔徑之影響 93 5.3.4 改變觸媒球顆粒粒徑之影響 99 5.3.5 不同進氣條件之影響 106 第六章 輸送係數關聯性之探討 113 6.1 輸送係數之計算 114 6.1.1 流力輸送係數 114 6.1.2熱傳輸送係數 115 6.1.3質傳輸送係數 116 6.2 輸送係數與文獻關聯式之比較 118 6.2.1 流力 118 6.2.2 熱傳 120 6.2.3 質傳 122 6.2.3.1 擴散 123 6.2.3.2 對流及擴散 130 第七章 結論 137 符號說明 141 參考文獻 147 圖目錄 圖4-1 填充式反應器觸媒顆粒配置圖,N=4.8637 10 圖4-2 填充式反應器網格圖 11 圖4-3 觸媒顆粒網格繪製示意圖 11 圖5-1 觸媒填充床式反應器之討論截面 26 圖5-2 個案1壓力分佈:S-A、S-B截面 40 圖5-3 個案1壓力分佈:S-C、S-D截面 41 圖5-4 個案1壓力分佈:S-E截面 42 圖5-5 個案1壓力分佈:S-F~S-J截面 43 圖5-6 個案1速度分佈:S-A、S-B截面 45 圖5-7 個案1速度分佈:S-C、S-D截面 46 圖5-8 個案1速度分佈:S-E截面 47 圖5-9 個案1溫度分佈:S-A、S-B截面 49 圖5-10 個案1溫度分佈:S-C、S-D截面 50 圖5-11 個案1溫度分佈:S-E截面 51 圖5-12 個案1溫度分佈:S-F~S-J截面 52 圖5-13 個案1 CH4組成分佈:圖 S-A、S-B截面 54 圖5-14 個案1 CH4組成分佈:S-C、S-D截面 55 圖5-15 個案1 CH4組成分佈:S-E截面 56 圖5-16 個案1 CH4組成分佈:S-F~S-J截面 57 圖5-17 個案1 H2O組成分佈:S-A、S-B截面 58 圖5-18 個案1 H2O組成分佈:S-C、S-D截面 59 圖5-19 個案1 H2O組成分佈:S-E截面 60 圖5-20 個案1 H2O組成分佈:S-F~S-J截面 61 圖5-21 個案1 CO組成分佈:S-A、S-B截面 62 圖5-22 個案1 CO組成分佈:S-C、S-D截面 63 圖5-23 個案1 CO組成分佈:S-E截面 64 圖5-24 個案1 CO組成分佈:S-F~S-J截面 65 圖5-25 個案1 H2組成分佈:S-A、S-B截面 66 圖5-26 個案1 H2組成分佈:S-C、S-D截面 67 圖5-27 個案1 H2組成分佈:S-E截面 68 圖5-28 個案1 H2組成分佈:S-F~S-J截面 69 圖5-29 個案1 CO2組成分佈:S-A、S-B截面 70 圖5-30 個案1 CO2組成分佈:S-C、S-D截面 71 圖5-31 個案1 CO2組成分佈:S-E截面 72 圖5-32 個案1 CO2組成分佈:S-F~S-J截面 73 圖5-33 個案1 O2組成分佈:S-A、S-B截面 74 圖5-34 個案1 O2組成分佈:S-C、S-D截面 75 圖5-35 個案1 O2組成分佈:S-E截面 76 圖5-36 個案1 O2組成分佈:S-F~S-J截面 77 圖5-37 Case 1與Case 8速度分佈比較:S-C截面 82 圖5-38 Case 1與Case 8壓力分佈比較:S-C截面 83 圖5-39 Case 1與Case 8溫度分佈比較:S-C截面 84 圖5-40 Case 1與Case 8 CH4組成分佈比較:S-C截圖 85 圖5-41 Case 1與Case 8 H2組成分佈比較:S-C截圖 86 圖5-42 Case 5與Case 9速度分佈比較:S-C截面 88 圖5-43 Case 5與Case 9溫度分佈比較:S-C截面 89 圖5-44 Case 5與Case9壓力分佈比較:S-C截面 90 圖5-45 Case 5與Case 9 CH4組成分佈比較:S-C截面 91 圖5-46 Case 5與Case 9 H2組成分佈比較:S-C截面 92 圖5-47 Case 1與Case 4速度分佈比較:S-C截面 94 圖5-48 Case 1與Case 4溫度分佈比較:S-C截面 95 圖5-49 Case 1與Case 4壓力分佈比較:S-C截面 96 圖5-50 Case 1與Case 4 CH4組成分佈比較:S-C截面 97 圖5-51 Case 1與Case 4 H2組成分佈比較:S-C截面 98 圖5-52 Case 4與Case 7速度分佈比較:S-C截面 101 圖5-53 Case 4與Case 7壓力分佈比較:S-C截面 102 圖5-54 Case 4與Case 7溫度分佈比較:S-C截面 103 圖5-55 Case 4與Case 7 CH4組成分佈比較:S-C截面 104 圖5-56 Case 4與Case 7 H2組成分佈比較:S-C截面 105 圖5-57 Case 1與Case 6速度分佈比較:S-C截面 108 圖5-58 Case 1與Case 6壓力分佈比較:S-C截面 109 圖5-59 Case 1與Case 6溫度分佈比較:S-C截面 110 圖5-60 Case 1與Case 6 CH4組成分佈比較:S-C截面 111 圖5-61 Case 1與Case 6 H2組成分佈比較:S-C截面 112 圖6-3 質傳係數(Sh_D)之比較,CH4 124 圖6-4 質傳係數(Sh_D)之比較,H2O………………………………………………..125 圖6-5 質傳係數(Sh_D)之比較,CO………………………………….……………..126 圖6-6 質傳係數(Sh_D)之比較,H2…………………...……………………………..127 圖6-7 質傳係數(Sh_D)之比較,CO2………………………………………………..128 圖6-8 質傳係數(Sh_D)之比較,O2…...……………………………………………..129 圖6-9 質傳係數(Sh_T)之比較,CH4………………………………………………..131 圖6-10 質傳係數(Sh_T)之比較,H2O…………..…………………………………..132 圖6-11 質傳係數(Sh_T)之比較,CO………………..……………….……….……..133 圖6-12 質傳係數(Sh_T)之比較,H2………………...………………..……………..134 圖6-13 質傳係數(Sh_T)之比較,CO2………………..……………………………..135 圖6-14 質傳係數(Sh_T)之比較,O2…...………………………..…………………..136 表目錄 表3-1 氫氣生成系統反應速率常數之參數值 8 表3-2 氫氣生成系統吸附係數之參數值 8 表4-1 填充式反應器尺寸與網格設定 12 表4-2 邊界條件 16 表4-3 使用之離散方法 21 表4-4 低鬆弛因子設定 22 表4-5 收斂準則 23 表5-1 個案彙整表 25 表5-2 各個案進口物流條件 27 表5-3 反應程度-氫氣生成量 (kmole/s.kgcat) 28 表5-4 有效因子 (R-1) 30 表5-5 有效因子 (R-2) 30 表5-6 有效因子 (R-3) 31 表5-7 有效因子 (R-4) 31 表5-8 CH4質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 33 表5-9 H2O質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 34 表5-10 CO質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 35 表5-11 H2質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 36 表5-12 CO2質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 37 表5-13 O2質傳量 (kg/s) (自觸媒顆粒至管中流體為正值) 38 表5-14 改變觸媒顆粒表面條件對反應程度-氫氣生成量之影響 78 表5-15 改變觸媒顆粒表面條件對CH4 (kg/s)質傳量之影響 79 表5-16 改變觸媒顆粒表面條件對H2O (kg/s)質傳量之影響 79 表5-17 改變觸媒顆粒表面條件對CO (kg/s)質傳量之影響 79 表5-18 改變觸媒顆粒表面條件對H2 (kg/s)質傳量之影響 80 表5-19 改變觸媒顆粒表面條件對CO2 (kg/s)質傳量之影響 80 表5-20 改變觸媒顆粒表面條件對O2 (kg/s)質傳量之影響 80 表5-21 改變雷諾數對反應程度-氫氣生成量之影響 87 表5-22 改變孔徑對反應程度-氫氣生成量之影響 93 表5-23 改變觸媒球粒徑對反應程度-氫氣生成量之影響 (kmole/s.kgcat) 100 表5-24 有效因子 (R-1) 100 表5-25 有效因子 (R-2) 100 表5-26 有效因子 (R-3) 100 表5-27 有效因子 (R-4) 100 表5-28 不同進氣條件對反應程度-氫氣生成量之影響 (kmole/s.kgcat) 107 表5-29 有效因子 (R-1) 107 表5-30 有效因子 (R-2) 107 表5-31 有效因子 (R-3) 107 表5-32 有效因子 (R-4) 107 |
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