Flow patterns and their transition characteristics of the air-water two-phase flow in a horizontal pipe with a sudden-changed cross-section area

Flow patterns and their transition characteristics of the air-water two-phase flow in a horizontal pipe with a sudden-changed cross-section area 1 2 first-author 1 3 1 1 State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, 710049 State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, 710049 Northwest Power Design Institute, Xi'an, 710068 Northwest Power Design Institute, Xi'an, 710068 School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT, UK School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT, UK Flow patterns in upstream and downstream straight tubes of sudden-changed areas in a horizontal straight pipe were experimentally examined. Both sudden-expansion cross-section (SECS) and sudden-contraction cross-section (SCCS) were investigated. The flow pattern maps upstream and downstream were delineated and compared with those in straight tubes with uniform cross-sections. The effects of the SECS and SCCS on flow patterns were discussed and analyzed. Furthermore, flow pattern transition mechanisms resulting in occurrences of different flow patterns were simply discussed and some transition criteria for the flow pattern transitions were deduced by using the non-dimensionlized analysis method. Gas-liquid two-phase flow Flow pattern Sudden-expansion cross-section Sudden-contraction cross-section References Tong L S , Tang Y S . Boiling heat transfer and two-phase flow ( 2nd ed). Taylor and Francis , 1997 Boiling heat transfer and two-phase flow Govier C W , Omier M M . Can J Chem Eng , 1962 , 49 : 93 ~ 104 Can J Chem Eng Weisman J , Duncan D , Gibson J et al . Int J Multiphase Flow , 1979 , 5 : 437 ~ 462 Int J Multiphase Flow Weisman J , Kang S Y . Int J Multiphase Flow , 1981 . 7 : 271 - 291 Int J Multiphase Flow Salcudean M , Chun J H , Groeneveld D C . Int J Multiphase Flow , 1983 . 9 : 87 - 90 Int J Multiphase Flow Guo L J , Li G J , Chen X J . J Xi'an Jiaotong University (in Chinese) , 1997 , 31 : 54 ~ 60 J Xi'an Jiaotong University (in Chinese) Chen X J , Chen L X , Zhou F D . Two-phase flow and heat transfer fundamentals (in Chinese) Beijing : Science Press , 1995 . Two-phase flow and heat transfer fundamentals (in Chinese) Yang Y Z . MS thesis , Xi'an Jiaotong University , 1994 MS thesis Moissis R , Griffith P . J Heat Transfer , 1962 . 84 : 29 - 39 J Heat Transfer Taitel Y , Dukler A E . AICHE J , 1976 , 22 : 47 - 55 AICHE J Dukler A E , Taitel Y . Flow pattern transitions in gas-liquid system: Measurement and modelling . In: Multiphase Science and Technology , Vol.2 , Hewitt G.F . et al ed. 1986 , 1 ~ 94 Flow pattern transitions in gas-liquid system: Measurement and modelling O359 + .1, V211.1 + 7, TL334 Support by the National Natural Science Foundation (No.59995460) 1999-09-12 2001-02-01 2021-02-05 2001 Nuclear Science and Techniques 1 12