Abstract
This paper describes an experimental investigation in which the cross-sectional two-phase flow structure during condensation of steam inside various inclined tubes was visualized using an axial-viewing technique and a high-speed camera. The two-phase flow structure was visualized along the axis of the condensation tube by locating the camera in front of the viewer that was fitted at the outlet of the tube where a short section of it was illuminated. This innovative technique permitted direct viewing into the flow and imaging of the cross-sectional area in a pipe of 16.55 mm inner diameter at atmospheric pressure and a saturation temperature of 100 °C. The downward inclination angle of the condensation tube in this study was varied from 3° to 75°, and three steam qualities, with values of 0.17, 0.34, and 0.78, were examined at the outlet of the pipe. A visualization test was conducted at a low steam mass flux of 3.43 kg/m2 s. Cross-sectional two-phase flow was clearly visible and identified easily over the range of inclination angles used; stratified-wavy flow was the most commonly observed flow pattern. Also, downward inclination had a significant effect on condensation parameters, such as void fraction, wetted angle, and bottom film thickness, which, in turn, showed that gravitational effects may improve condensation phenomena.
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Abbreviations
- θ wet :
-
Condensate wetted angle around the condensate layer at the bottom (°)
- θ inc :
-
Downward inclination angle (°)
- h fg :
-
Latent heat (J/kg)
- L :
-
Length (m)
- \(\dot{m}_{\text{cw}}\) :
-
Mass flow rate of cooling water (kg/s)
- x :
-
Steam quality
- R :
-
Radius (m)
- T :
-
Temperature (°C)
- ΔT :
-
Temperature difference (°C)
- \(\dot{m}_{S}\) :
-
Steam mass flow rate (kg/s)
- V L :
-
Volume of liquid inside the pipe (m3)
- α :
-
Void fraction
- \(\delta\) :
-
Bottom film thickness (m)
References
Ahn T-H, Yun BJ, Jeong JJ (2014) Development of a new condensation model for the nearly-horizontal heat exchanger tube under the steam flowing conditions. Int J Heat Mass Transf 79:876–884
Ahn T-H, Yun BJ, Jeong JJ (2015) Void fraction prediction for separated flows in the nearly horizontal tubes. Nucl Eng Technol 47:669–677
Arnold CR, Hewitt GF (1967) Further developments in the photography of two phase gas-liquid flow. J Photogr 15:97–114
Azzopardi BJ (1987) Observations of drop motion in horizontal annular flow. Chem Eng Sci 8:2059–2062
Badie S (2000) Horizontal stratifying/annular gas–liquid flow. Thesis for Doctor of Philosophy of the University of London, Imperial College of Science, Technology and Medicine, London
Cartellier A (1990) Optical probes for local void fraction measurements: characterization of performance. Rev Sci Instrum 61:874–886
Cartellier A (1997) Measurements of gas phase characteristics using new monofiber optical probes and real time signal processing. Proceedings of the OECD/CSNI specialist meeting on advanced instrumentation and measurement techniques, Santa Barbara, 17–20 Mar 1997
Cavallini G, Censi D, Del Col L, Doretti GA, Rossetto Longo L (2002) In-tube condensation of halogenated refrigerants. ASHRAE Trans 108:146–161
Charlety P (1971) Ebullition du Sodium en Convection Forcee. These de Docteur Ingeniur, Faculte des Sciences, Universite de Grenoble
Collier J, Thome R (1994) Convective boiling and condensation. Clarendon Press, Oxford
Costigan G, Wade CD (1984) Visualization of the Reflooding of a vertical tube by dynamic neutron radiography. Int. Workshop on Fundamental Aspects of Post-Dryout Heat Transfer, Salt Lake City, pp 2–101
Costigan G, Whalley PB (1997) Slug flow regime identification from dynamic void fraction measurements in vertical air–water flows. Int J Multiph Flow 23:263–282
Delhaye JM, Achard JL (eds) (1977) On the average operators introduced in two-phase flow modeling, transient two-phase flow. Proceedings of the CSNI Specialists Meeting
Delhaye JM (1986) Recent advances in two-phase flow instrumentation. Heat Transf 1:215–226
Fisher SA, Yu S (1975) Dryout in serpentine evaporators. Int J Multiph Flow 1:771–791
Gardner RP, Bean RH, Ferrel JL (1970) On the gamma-ray one-shot-collimator measurement of two-phase flow void fraction. Nucl Appl Technol 8:88–94
Garnier J (1997) Measurement of local Flow pattern in boiling R12 simulating PWR conditions with multiple optical probes. Proceedings of the OECD/CSNI specialist meeting on advanced instrumentation and measurement techniques, Santa Barbara, 17–20 Mar 1997
Govan AH, Hewitt GF, Ngan CF (1989) Particle motion in a turbulent pipe flow. Int J Multiph Flow 3:471–481
Hewitt GF, Roberts DN (1969) Investigation of interfacial phenomena in annular two-phase flow by means of the axial view technique. UK AEA report, AERE R6070
Jeandey C (1982) Multibeam X-ray densitometer for flow pattern and void fraction determination in steam-water mixtures. Measur Polyph Flows 209:19–28
Jeon SS, Hong SJ, Park JY, Seul KW, Park GC (2011) Assessment of horizontal in-tube condensation models using MARS code. Part I: stratified flow condensation. Nucl Eng Des 254:254–265
Kendoush A (2002) Void fraction measurement by X-ray absorption. Exp Thermal Fluid Sci 25:615–621
Lips S, Meyer J (2011) Two-phase flow in inclined tubes with specific reference to condensation: a review. Int J Multiph Flow 37:845–859
Lips S, Meyer J (2012a) A stratified flow model for convective condensation in an inclined tube. Int J Heat Fluid Flow 36:83–91
Lips S, Meyer J (2012b) Experimental study of convective condensation in an inclined smooth tube: inclination effect on flow pattern and heat transfer coefficient. Int J Heat Mass Transf 55:395–404
Lockhart RW, Martinelli RC (1949) Proposed correlation of data for isothermal two-phase, two component flow in pipes. Chem Eng Progr 45:39–48
McQuillan KW, Whalley PB, Hewitt GF (1985) Flooding in vertical two-phase flow. Int J Multiph Flow 11:741–760
Merilo M, Dechene RL, Cichowlas WM (1977) Void fraction measurement with a rotating field conductance gauge. J Heat Transf 99:330–332
Meyer J, Dirker J, Adelaja A (2014) Condensation heat transfer in smooth inclined tubes for R134a at different saturation temperatures. Int J Heat Mass Transf 70:515–525
Mishima K, Hibiki T (1997) Development of high-frame rate neutron radiography and quantitative measurement method for multiphase flow research. Proceedings of the of the OECD/CSNI specialist meeting on advanced instrumentation and measurement techniques, Santa Barbara, 17–20 Mar 1997
Nyer M (1969) Etude des Phenomenes Thermiques et Hydrauliques Accompagnant une Excursion rapide de Puissance sur un Canal Chauffant. CEA-R 3497
Olivier S, Meyer J, De Paepe M, De Kerpel K (2016) The influence of inclination angle on void fraction and heat transfer during condensation inside a smooth tube. Int J Multiph Flow 80:1–14
Rouhani SZ, Axelsson E (1970) Calculation of void volume fraction in the subcooled and quality boiling regions. Int J Heat Mass Transfer 13:383–393
Schleichera E, Tayfun B, Vieira R, Torres C, Pereyra E, Saricab C, Hampela U (2015) Refined reconstruction of liquid–gas interface structures for stratified two-phase flow using wire-mesh sensor. Flow Meas Instrum 46:230–239
Snell CS, Dechene RL, Newton RE (1978) Two-phase relative volume fraction measurement with a rotating field conductance gauge. Meas Polyph Flows 21–24
Takenaka N, Fujii T, Akagawa K, Ono A, Sonoda K, Nishizaki K, Asano H (1990) Application of neutron radiography to visualization of multiphase flows. Flow Meas Instrum 1:149–156
Thome JR, El Hajal J, Cavallini A (2003) Condensation in horizontal tubes, part 2: new heat transfer model based on flow regimes. Int J. Heat Mass Transf 46:3365–3387
Yoneda K, Kawai T, Fujine S, Uturo M, Ikeda Y, Yokoi M, Kobayashi H (1990) Cold neutron hole in KUR and its radiography tests. Proc. 1st. Int. Top. Meet. Neutron Radiography System Design and Characterization, Ontario. Canada, p 32–42
Zeng Y, Hale CP, Walker SP, Hewitt GF (2010) Design of a high temperature axial viewing system for experimental studies of single tube reflood. 7th international conference on multiphase flow, ICMF 2010, Tampa, 30 May–4 June
Zivi SM (1964) Estimation of steady state steam void fraction by means of the principle of minimum entropy production. Trans ASME J Heat Transf 86:247–252
Acknowledgements
This research was supported by the nuclear R&D program supported by the Ministry of Trade, Industry and Energy of the Korean government (No. 20141510400060). Also, it was supported by “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry and Energy, Republic of Korea (No. 20164030200990).
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Pusey, A., Kim, D., Park, HS. et al. Visualization method for cross-sectional two-phase flow structure during the condensation of steam in a tube. J Vis 20, 591–605 (2017). https://doi.org/10.1007/s12650-016-0408-0
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DOI: https://doi.org/10.1007/s12650-016-0408-0