臺灣博碩士論文加值系統

新冠狀病毒（縮寫：COVID-19）從2019年起在全球肆虐，至今科學家們持續研究，嘗試理解病毒的組成及傳播途徑，為的就是降低疫情對人們造成的傷害。近年來有研究懷疑防疫旅館是否會有病毒傳播、感染的可能性，因此本研究利用Ansys Fluent模擬病毒粒子在密閉空調環境中的傳播情形。
本論文模擬中央空調及天花板縫傳播病毒的可能性，此研究是基於人們在住宿時，聞到了煙味而提出的疑惑。研究中利用CFD數值方法模擬冠狀病毒粒子在旅館房間的擴散，觀察病毒的擴散情形，研究病毒粒子是否會傳播到相鄰的房間。
經過研究得到以下結論，在中央空調系統中若回風口所帶出之空氣是經由管道完全排出的條件下，病毒粒子無法藉由中央空調系統進行傳播。在此模擬基礎下，進而衍生出天花板縫隙是否可能作為病毒傳播途徑的討論，結果顯示，即使是微小的縫隙也有足夠的能力傳播病毒，進而增加染疫的風險。
接著本文進一步探討在房間的各個角落加上清淨機來觀察不同位置的清淨機是否能有效阻擋病毒顆粒擴散到相鄰的房間，模擬結果顯示放置在牆上的清淨機能有效的減少病毒的傳播，但依然無法完全阻隔。最終在縫隙上方加一出風口，探討運用氣幕的方式是否能阻隔病毒，結果顯示此方法在模擬的三分鐘內能有效得阻隔病毒。

This paper simulates the possibility of virus transmission from central air conditioners and ceiling cracks. This research is based on the doubts raised by people who smell smoke when they are staying. We use CFD numerical method to simulate whether the coronavirus would spread to adjacent rooms.
The following conclusions were obtained. The virus particles cannot be transmitted through the central air-conditioning system. This simulation also showed that even small gaps have sufficient capacity to transmit the virus, thereby increasing the risk of infection.
Then this paper further explores adding cleaners to each corner of the room to observe whether the cleaners at different positions can effectively prevent virus particles from spreading to adjacent rooms. The simulation results show that the cleaners placed on the wall can effectively reduce the spread of viruses. But it still cannot be completely blocked. Finally, an air outlet was added above the gap to explore whether the air curtain could block the virus. The results showed that this method could effectively block the virus within three minutes of the simulation.

摘要 i
ABSTRACT ii
誌謝 iii
目錄 iv
表目錄 vii
圖目錄 viii
1 第一章 緒論 1
1.1 研究背景與目的 1
1.2 氣溶膠 1
1.3 冠狀病毒病COVID-19 2
1.3.1 COVID-19症狀 3
1.3.2 COVID-19的突變 4
1.4 文獻探討 4
1.5 本文的主要內容 5
2 第二章 病毒擴散的數值計算方法 6
2.1 基本控制方程 6
2.1.1 質量守恆方程式 7
2.1.2 動量守恆方程式 8
2.2 紊流模型 9
2.2.1 紊流的概述 9
2.2.2 紊流分類 10
2.2.3 雷諾平均Navier-Stokes（RANS）模型 11
2.2.4 渦黏模型 12
2.2.5 k-ε模型 14
2.3 離散項顆粒概述 17
2.3.1 顆粒運動方程 18
2.4 數值計算的離散方法 21
2.4.1 有限體積法 21
2.4.2 有限差分法 22
2.4.3 有限元素法 22
2.5 控制方程求解技術 23
2.5.1 SIMPLE算法 23
2.5.2 PISO算法 24
3 第三章 情境描述及參數設定 26
3.1 模擬流程 26
3.2 基本假設 27
3.3 模型建立及情境描述 28
3.3.1 CASE_1 正常室內中央空調建模 28
3.3.2 CASE2_天花板門縫對氣溶膠分佈的影響建模 29
3.3.3 CASE_3空氣清淨機對氣溶膠影響建模 31
3.3.4 CASE_4氣幕對氣溶膠影響建模 33
3.4 網格劃分 34
3.4.1 網格敏感度分析 35
3.4.2 CASE_1 正常室內中央空調網格 37
3.4.3 CASE2_天花板門縫對氣溶膠分佈的影響網格 37
3.4.4 CASE_3空氣清淨機對氣溶膠影響網格 39
3.4.5 CASE_4氣幕對氣溶膠影響網格 41
3.5 邊界條件及參數設定 41
3.5.1 數值仿真方法 43
4 第四章 結果與討論 45
4.1 CASE_1 正常室內中央空調結果 45
4.2 CASE2_天花板門縫對氣溶膠分佈的影響結果 48
4.2.1 案例2-1結果 48
4.2.2 案例2-2結果 52
4.2.3 案例2-3結果 56
4.3 CASE_3空氣清淨機對氣溶膠影響結果 60
4.3.1 案例3-1結果 61
4.3.2 案例3-2結果 65
4.3.3 案例3-3結果 69
4.3.4 案例3-4結果 72
4.4 CASE_4氣幕對氣溶膠影響結果 76
5 第五章 結論 81
參考文獻 82

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