在此研究中，以實驗方式研究垂直圓管上升氣水雙相流流譜量測與鑑別，利用壓力信號、差壓信號以及電導度信號所做量測信號的特性分析，並同時設有觀測段可供照相、攝影作為對比使用。目前尚未有完整偵測流譜信號的方法，故透過建立大量的實驗數據庫，並對實驗範圍內各種流譜進行流譜特性分析，期望能夠得到客觀的雙相流流譜鑑別方法用於非侵入式的感測器偵測。本研究將專注於攪拌流的流譜特性分析，顧名思義其流譜動態過程看似空氣與水流動過程有互相攪拌的行為，因此其物理特性相較其他流譜複雜，在過去的研究中鮮少有特別研究攪拌流譜的特性分析，著名的雙相流譜Taitel and Dukler以及Mishima and Ishii皆有區別攪拌流，但兩者的範圍有極大的差異，同時也說明了攪拌流譜在雙相流的複雜程度。
過去大部分學者認為攪拌流僅是彈狀流與環狀流的流轉轉換過程，但經詳細觀察，本研究的初步認為攪拌流應在流譜圖再細分為兩種流譜，此兩種的物理行為迥異，目前分別命名為低水流速攪拌流與高水流速攪拌流，首先低水流速攪拌流較為接近彈狀流與環狀流的轉換過程的中間流譜，行為單純隨著氣流速增加，泰勒氣泡逐漸增長至互相連接形成環狀流。後者物理行為更為複雜，本研究認為在高水流速攪拌流中除了變形泰勒氣泡與氣水混和段外，有一群中型氣泡的穩定存在，形狀不規則、空泡分率約小於0.65，其在流譜中的佔比會隨著氣、水比例不同變化，因此本研究特別發展信號分析方法，希望透過客觀的訊號分割三種不同流態，分別使用信號處理以及統計研究高水流速攪拌流的特性。

Two-phase flow in a vertical pipe can be divided into several flow patterns, such as bubbly flow, slug flow, churn flow, annular flow and wispy-annular flow with increasing gas superficial velocity, respectively. However, some of the transitions and/or definitions of flow regimes are still debating or unclear. Some researchers may consider that churn flow was just a transition of slug flow and annular flow. Actually, there is not only a lot of complicated interactions between water and gas, but also there are some unique characteristics for churn flow. To figure out the complicity of churn and annular flows as long as to understand the interactions between two phases among these flow regimes are indispensable.
In this study, the operating condition of adiabatic two phase flow experiment is at normal temperature and pressure. During the experiments, air and water flowed into a 30mm diameter, 5m height vertical pipe by controlling water and air volume flow rate. And several conductivity sensors and differential pressure sensors were used to record. In addition to signal, some photos and videos were token by high frame rate camera and high speed camcorder in the visualization region. A signal process for high water flow rate churn flow was developed successfully and the results of the signal process showed the distinguished characteristic of high water flow rate churn flow.

摘要 ii
Abtract iii
目錄 iv
圖目錄 vi
表目錄 x
符號說明 xi
第一章 緒論 1
1.1 前言 1
1.2 雙相流簡介 2
1.2.1 雙相流基本性質 2
1.2.2 流譜分類(flow regime/ flow pattern) 2
1.3 研究目的與方法 5
第二章 文獻回顧 7
2.1 攪拌流研究 7
2.2 彈狀流/攪拌流研究 13
2.3 環狀流/攪拌流研究 17
2.4 小結 18
第三章 實驗系統與實驗步驟 19
3.1 實驗設備 19
3.1.1 空氣供給系統 20
3.1.2 冷水供給系統 22
3.1.3 流譜測試段系統 23
3.1.4 量測信號系統 25
3.1.5 資料擷取系統 26
3.2 實驗流速範圍 26
3.3 實驗步驟 27
第四章 分析方法 29
4.1 空泡分率信號與驗證 29
4.2 機率密度分佈圖 32
4.3 PDF模組參數化 34
4.4 PDF雙峰模組參數化 37
4.5 PDF雙峰模組參數化流譜圖驗證 39
4.6 高水流速攪拌流之區域定義 41
4.7 攪拌流譜訊號處理 47
第五章 結果與討論 59
第六章 結論 71
第七章 參考文獻 73

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