輻射相關應用的使用現今已經非常地廣泛；像是醫療檢查和治療、食品工業或者更為複雜的高科技應用都可以發現輻射應用為人類文明所帶來的貢獻。本論文是以中子照相的方式觀察在金屬管內垂直向上和水平和的雙向流特性。清華大學擁有穩定且高品質的熱中子源(清華大學水池式反應器THOR)能夠支援本實驗中子照相需要。

中子照相是利用中子和物質作用的特性，和X光不同，幾乎所有中子和金屬的作用截面都低於X光；所以可以輕易地穿過金屬管，但卻容易和水起反應而被水所阻擋；本論文就是透過中子和物質作用的這種特性來觀察金屬管內的雙向流情況進而計算空泡分率。

由於，中子照相的成像性質很適合用來估計空泡分率、氣泡上升速率的分析；所以本論文著重在中子照相的影像處理和空泡分率的計算結果與比較。

The applications of radiation have been quite extensive recently. Such as medical check-ups,therapies, the food industry and even more complicated technological applications can justify the contributions to human civilization which was brought by radiation. The paper observes the bidirectional property which is vertical and horizontal in the metal pipe by neutron radiography. National Tsing Hua University is equipped with stable and high quality thermal neutron(THOR) which can support the need of neutron radiography in this experiment.

Neutron radiography utilizes the attribution of the interaction between neutrons and other materials. Compared to X-ray,almost neutrons interact cross section with metal is low than X-ray; therefore, they can easily pass through the metal pipe. Neutrons, however, easily interact with water and the are blocked by water. The paper calculates the void fraction by observing the bidirectional property in the metal pipe that results from the different interactions between different neutrons and materials.

Since the imaging Properties is very suitable to estimate and analyze void fraction、bubble rising velocity. That is, the paper put emphasis on neutron radiography and the comparison of void fraction.

致謝 i
摘要 ii
Abstract iii
目錄 i
表目錄 iv
圖目錄 v
第一章 緒論 1
1.1 前言 1
1.2 文獻回顧 2
1.3 研究動機與實驗流程 4
第二章 實驗原理 6
2.1 中子照相簡介 6
2.2 雙相流介紹 19
第三章 實驗儀器設備與影像處理程式OpenCV介紹 25
3.1 清華大學水池式反應器(THOR)中子照相設備介紹 25
3.2 氣水雙相流實驗系統介紹 28
3.3 實驗儀器介紹 29
3.3.1 PUMP介紹 29
3.3.2 測量儀器介紹 30
3.3.3 電導度計信號分析 30
3.4 影像處理程式OpenCV介紹 31
第四章 實驗結果與討論 36
4.1 實驗流程 36
4.2 中子照相特性與成像品質 38
4.3 影像處理之野點與雜訊消除 41
4.4 影像處理之平均灰階值 47
4.5 影像處理之空泡分率計算 48
4.6 野點與雜訊消除和灰階值平均效果 54
4.7 體積權重的效果 58
4.8 垂直狀態 62
4.9 水平狀態 69
4.10 電導度計量測 77
4.11 實驗與理論比較 78
第五章 結論與建議 81
5.1 結論 81
5.2 建議 83
參考文獻 85
附錄 88
光學拍攝 88
垂直(jG = 0.1062、jL = 0) 88
水平(jG = 0.0981、jL = 0) 89
中子照相相片 90
垂直 90
水平 92
程式碼 94
雜訊及野點處理 94
空泡分率計算 110

中子照相相關：

[1] A.A. Harms, D.R. Wyman, “Mathematics and Physics of Neutron Radiography”, D. Reidel Publishing, U.S.A and Canada, (1986).
[2] T. Hibiki, K. Mishim, “Feasibility of high frame-rate neutron radiography by using a
steady thermal neutron beam with 106 n/(cm2 s) flux”, Nuclear Instruments and Methods in Physics Research, A 369, (1996) , 186-194.
[3] K. Mishim, T. Hibiki, “Quantitative Limits of Thermal and Fluid Phenomena Measurements Using the Neutron Attenuation Characteristics of Materials”, Experimental Thermal and Fluid Science, 12, (1996), 461-472.
[4] K. Mishima , T. Hibiki, “Development of high-frame-rate neutron radiography and quantitative measurement method for multiphase flow research”, Nuclear Engineering and Design, 184, (1998), 183–201.
[5] J.S. Brenizer, H. Berger, K.M. Gibbs, P. Mengers, C.T. Stebbings, D. Polansky, D.J. Rogerson, “Development of a new electronic neutron imaging system”, Nuclear Instruments and Methods in Physics Research, A 424, (1999), 9-14.
[6] Harold Berger, “Advances in neutron radiographic techniques and applications : a method for nondestructive testing”, Applied Radiation and Isotopes, 61, (2004), 437–442.
[7] D. Kramer, E. Lehmann, G. Frei, P. Vontobel, A. Wokaun, G.G. Scherer, “An on-line study of fuel cell behavior by thermal neutrons”, Nuclear Instruments and Methods in Physics Research, A 542, (2005), 52–60.
[8] J.R. Buell, D.P Byskal, M.R. Desrosiers, E.M.A. Hussein, P.J. Ingham, R.S. Swartz, “A neutron scatterometer for void-fraction measurement in heated rod-bundle channels under CANDU LOCA conditions”, International Journal of Multiphase Flow, 31, (2005), 452–472.
[9] N. Kardjilov, A.Hilger, I.Manke, M.Strobl, M.Dawson, S.Williams, J.Banhart, “Neutron tomography instrument CONRAD at HZB”, Nuclear Instruments and Methods in Physics Research, A 651, (2011), 47–52.
[10] Danyal Turkoglu, Lei Cao, Radoslaw Lewandowski, “A low-cost neutron radiography device”, Physics Procedia, 43, 2013, 54 – 65.
[11] F. Fusseis, X. Xiao, C. Schrank, F. De Carlo, “A brief guide to synchrotron radiation-based microtomography in(structural) geology and rock mechanics”, Journal of Structural Geology, 65, (2014), 1-16.

雙相流相關：

[12] KAICHIRO MISHIMA, “FLOW REGIME TRANSITION CRITERIA FOR UPWARD TWO-PHASE FLOW IN VERTICAL TUBES”, Int. J. Heat Mass Transfer Vol. 27, No. 5, (1984), 723-731.
[13] K JELL H. BENDIKSENJ, “AN EXPERIMENTAL INVESTIGATION OF THE MOTION OF LONG BUBBLES IN INCLINED TUBES”, Int. J. Multiphase Flow Vol. 10, No. 4, (1984), 467-483.
[14] D. BARNEA, O. SHOHAM, Y. TAITEL, A.E. DUKLER,” GAS-LIQUID FLOW IN INCLINED TUBES: FLOW PATTERN TRANSITIONS FOR UPWARD FLOW”, Chemical Engineering Science Vol. 40, No. I, (1985), 131-134.
[15] K. MISHIMA, T. HIBIKI,” SOME CHARACTERISTICS OF AIR-WATER TWO-PHASE FLOW IN SMALL DIAMETER VERTICAL TUBES”, lnt. J. Multiphase Flow Vol. 22, No. 4, 1996, 703-712.
[16] Hideo NAKAMURA, “Slug Flow Transitions in Horizontal Gas/Liquid Two-phase Flows(Dependence on Channel Height and System Pressure for Air/Mater and Steam/Water Two-phase Flows)”, JAERI-Research, 96-022.
[17] L.E. Gomez, Ovadia Shoham, Zelimir Schmidt, R.N. Chokshi, Tor Northug, “Unified Mechanistic Model for Steady-State Two-Phase Flow: Horizontal to Vertical Upward Flow”, SPE Journal Vol. 5, No. 3, (2000), 339-350.
[18] XIA Guo-Dong, ZHOU Fang-De, HU Ming-Sheng, “Distribution of void fraction for gas-liquid slug flow in an inclined pipe”, NUCLEAR SCIENCE AND TECHNIQUES Vol.12, No.2 , (2001), 143-148.
[19] Hong-Quan Zhang, Qian Wang, Cem Sarica, James P. Brill, “A unified mechanistic model for slug liquid holdup and transition between slug and dispersed bubble flows”, International Journal of Multiphase Flow, 29, (2003), 97–107.
[20] CARL SUNDE, SENADA AVDIC, IMRE PÁZSIT, “CLASSIFICATION OF TWO-PHASE FLOW REGIMES VIA IMAGE ANALYSIS AND A NEURO-WAVELET APPROACH”, Progress in Nuclear Energy Vol. 46, No. 3-4, (2005), 348-358.
[21] Luiz Eduardo Melo Lima, Eugênio Spanó Rosa, “ONE DIMENSIONAL DRIFT FLUX MODEL APPLIED TO HORIZONTAL SLUG FLOW”, 20th International Congress of Mechanical Engineering, (2009).
[22] Jing-yu Xu, “A simple correlation for prediction of the liquid slug holdup in gas/non-Newtonian fluids: Horizontal to upward inclined flow”, Experimental Thermal and Fluid Science, 44, (2013), 893–896.
[23] Jinho Choi, Eduardo Pereyra, Cem Sarica, Changhyup Park, Joe M. Kang, “An Efficient Drift-Flux Closure Relationship to Estimate Liquid Holdups of Gas-Liquid Two-Phase Flow in Pipes”, Energies, 5, (2012), 5294-5306.
[24] 闫超星，阎昌琪，孙立成，幸奠川，刘国强，“倾斜通道内泡状流空泡份额分布特性”，化 工 学 报，第 65 卷 第 3 期，(2014)，855-861。

OpenCV相關：

[25]https://zh.wikipedia.org/zh-tw/OpenCV
[26]http://www.cmlab.csie.ntu.edu.tw/~jsyeh/wiki/doku.php?id=%E8%91%89%E6%AD%A3%E8%81%96%E8%80%81%E5%B8%AB:%E6%95%99%E7%A0%94%E7%A9%B6%E7%94%9F%E5%AD%B8opencv