0
Research Papers: Evaporation, Boiling, and Condensation

Numerical Simulation of Condensation for R410A in Horizontal Round and Flattened Minichannels

[+] Author and Article Information
Wei Li

Fellow ASME
Department of Energy Engineering,
Zhejiang University,
Hangzhou 310027, China
e-mail: Weili96@zju.edu.cn

Jingzhi Zhang, Junye Li

Department of Energy Engineering,
Zhejiang University,
Hangzhou 310027, China

Guanghui Bai

Huadian Electric Power Research
Institute
Zhejiang, Hangzhou 310030, China

Jin-liang Xu

The Beijing Key Laboratory of Multiphase
Flow and Heat Transfer for
Low Grade Energy Utilization,
North China Electric Power University,
Beijing 102206, China

Terrence W. Simon

Mechanical Engineering Department,
University of Minnesota,
111 Church Street S.E.,
Minneapolis, MN 55455

Jin-jia Wei

State Key Laboratory of Multiphase
Flow in Power Engineering,
Xi'an Jiaotong University,
Xi'an, 710049, China

Contributed by the Heat Transfer Division of ASME for publication in the JOURNAL OF HEAT TRANSFER. Manuscript received May 21, 2015; final manuscript received August 30, 2016; published online October 26, 2016. Assoc. Editor: Amitabh Narain.

J. Heat Transfer 139(2), 021501 (Oct 26, 2016) (9 pages) Paper No: HT-15-1352; doi: 10.1115/1.4034812 History: Received May 21, 2015; Revised August 30, 2016

Heat transfer characteristics for condensation for R410A inside horizontal round (dh = 3.78 mm) and flattened tubes (aspect ratio (AR) = 3.07, 4.23, and 5.39) with larger horizontal than vertical dimensions at a saturation temperature of 320 K are investigated numerically. The flattened tube has flat upper and lower walls and circular end walls. The heat and mass transfer model for condensation is verified by comparing numerical heat transfer coefficients of round tubes with experimental data and empirical correlations. Liquid–vapor interfaces and local heat transfer coefficients are also presented to give a better understanding of the condensation process inside these tubes. The results indicate that local heat transfer coefficients increase with increasing mass flux, vapor quality, and aspect ratio. The enhancement of heat transfer coefficients for flattened tubes is more pronounced at higher mass flux and vapor quality values (about 1.5 times the heat transfer coefficients for round tubes when G = 1061 kg m−2 s−1, x ≥ 0.8). Unlike in the round tubes, the liquid film in the flattened tube accumulates at the sides of the bottom surface and at the middle of the top surface of the channels when vapor quality is low. Peak values of liquid film thickness in flattened tubes are obtained around angles about the centroid θ of 70 deg and 117 deg, where θ = 0 deg is upward.

FIGURES IN THIS ARTICLE
<>
Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.

References

Garimella, S. , 2004, “ Condensation Flow Mechanisms in Microchannels: Basis for Pressure Drop and Heat Transfer Models,” Heat Transfer Eng., 25(3), pp. 104–116. [CrossRef]
El Hajal, J. , Thome, J. R. , and Cavallini, A. , 2003, “ Condensation in Horizontal Tubes—Part 1: Two-Phase Flow Pattern Map,” Int. J. Heat Mass Transfer, 46(18), pp. 3349–3363. [CrossRef]
Shah, M. M. , 1979, “ General Correlation for Heat-Transfer During Film Condensation Inside Pipes,” Int. J. Heat Mass Transfer, 22(4), pp. 547–556. [CrossRef]
Shah, M. M. , 2009, “ An Improved and Extended General Correlation for Heat Transfer During Condensation in Plain Tubes,” HVAC&R Res., 15(5), pp. 889–913. [CrossRef]
Dobson, M. K. , and Chato, J. C. , 1998, “ Condensation in Smooth Horizontal Tubes,” ASME J. Heat Transfer, 120(1), pp. 193–213. [CrossRef]
Cavallini, A. , Del Col, D. , Doretti, L. , Matkovic, M. , Rossetto, L. , Zilio, C. , and Censi, G. , 2006, “ Condensation in Horizontal Smooth Tubes: A New Heat Transfer Model for Heat Exchanger Design,” Heat Transfer Eng., 27(8), pp. 31–38. [CrossRef]
Cavallini, A. , Doretti, L. , Matkovic, M. , and Rossetto, L. , 2006, “ Update on Condensation Heat Transfer and Pressure Drop Inside Minichannels,” Heat Transfer Eng., 27(4), pp. 74–87. [CrossRef]
Doretti, L. , Zilio, C. , Mancin, S. , and Cavallini, A. , 2013, “ Condensation Flow Patterns Inside Plain and Microfin Tubes: A Review,” Int. J. Refrig., 36(2), pp. 567–587. [CrossRef]
Dalkilic, A. , and Wongwises, S. , 2009, “ Intensive Literature Review of Condensation Inside Smooth and Enhanced Tubes,” Int. J. Heat Mass Transfer, 52(15), pp. 3409–3426. [CrossRef]
Wu, Z. , Sundén, B. , Wang, L. , and Li, W. , 2014, “ Convective Condensation Inside Horizontal Smooth and Microfin Tubes,” ASME J. Heat Transfer, 136(5), p. 051504. [CrossRef]
Yan, Y. Y. , and Lin, T. F. , 1999, “ Condensation Heat Transfer and Pressure Drop of Refrigerant R-134a in a Small Pipe,” Int. J. Heat Mass Transfer, 42(4), pp. 697–708. [CrossRef]
Lee, H. , Mudawar, I. , and Hasan, M. M. , 2013, “ Flow Condensation in Horizontal Tubes,” Int. J. Heat Mass Transfer, 66, pp. 31–45. [CrossRef]
Wang, L. , Dang, C. , and Hihara, E. , 2012, “ Experimental Study on Condensation Heat Transfer and Pressure Drop of Low GWP Refrigerant HFO1234yf in a Horizontal Tube,” Int. J. Refrig., 35(5), pp. 1418–1429. [CrossRef]
Lee, H. , Kharangate, C. R. , Mascarenhas, N. , Park, I. , and Mudawar, I. , 2015, “ Experimental and Computational Investigation of Vertical Downflow Condensation,” Int. J. Heat Mass Transfer, 85, pp. 865–879. [CrossRef]
Naik, R. , and Narain, A. , 2016, “ Steady and Unsteady Simulations for Annular Internal Condensing Flows—Part II: Instability and Flow Regime Transitions,” Numer. Heat Transfer, Part B, 69(6), pp. 473–494. [CrossRef]
Naik, R. , Narain, A. , and Mitra, S. , 2016, “ Steady and Unsteady Simulations for Annular Internal Condensing Flows—Part I: Algorithm and Its Accuracy,” Numer. Heat Transfer, Part B, 69(6), pp. 495–510. [CrossRef]
Schrage, R. W. , 1953, A Theoretical Study of Interphase Mass Transfer, Columbia University, New York.
Lee, W. H. , 1980, A Pressure Iteration Scheme for Two-Phase Flow Modeling, Hemisphere, Washington, DC.
Ganapathy, H. , Shooshtari, A. , Choo, K. , Dessiatoun, S. , Alshehhi, M. , and Ohadi, M. , 2013, “ Volume of Fluid-Based Numerical Modeling of Condensation Heat Transfer and Fluid Flow Characteristics in Microchannels,” Int. J. Heat Mass Transfer, 65, pp. 62–72. [CrossRef]
Chen, S. , Yang, Z. , Duan, Y. , Chen, Y. , and Wu, D. , 2014, “ Simulation of Condensation Flow in a Rectangular Microchannel,” Chem. Eng. Process: Process Intensif., 76, pp. 60–69. [CrossRef]
Wang, H. S. , and Rose, J. W. , 2006, “ Film Condensation in Horizontal Microchannels: Effect of Channel Shape,” Int. J. Therm. Sci., 45(12), pp. 1205–1212. [CrossRef]
Da Riva, E. , and Del Col, D. , 2012, “ Numerical Simulation of Laminar Liquid Film Condensation in a Horizontal Circular Minichannel,” ASME J. Heat Transfer, 134(5), p. 051019. [CrossRef]
Da Riva, E. , Del Col, D. , Garimella, S. V. , and Cavallini, A. , 2012, “ The Importance of Turbulence During Condensation in a Horizontal Circular Minichannel,” Int. J. Heat Mass Transfer, 55(13–14), pp. 3470–3481. [CrossRef]
Bortolin, S. , Da Riva, E. , and Del Col, D. , 2014, “ Condensation in a Square Minichannel: Application of the VOF Method,” Heat Transfer Eng., 35(2), pp. 193–203. [CrossRef]
Phan, L. , Wang, X. , and Narain, A. , 2006, “ Effects of Exit-Condition, Gravity, and Surface-Tension on Stability and Noise-Sensitivity Issues for Steady Condensing Flows Inside Tubes and Channels,” Int. J. Heat Mass Transfer, 49(13–14), pp. 2058–2076. [CrossRef]
Wilson, M. J. , Newell, T. A. , Chato, J. C. , and Infante Ferreira, C. A. , 2003, “ Refrigerant Charge, Pressure Drop, and Condensation Heat Transfer in Flattened Tubes,” Int. J. Refrig., 26(4), pp. 442–451. [CrossRef]
Kim, N. H. , Lee, E. J. , and Byun, H. W. , 2013, “ Condensation Heat Transfer and Pressure Drop in Flattened Smooth Tubes Having Different Aspect Ratios,” Exp. Therm. Fluid. Sci., 46, pp. 245–253. [CrossRef]
Lee, E. J. , Kim, N. H. , and Byun, H. W. , 2014, “ Condensation Heat Transfer and Pressure Drop in Flattened Microfin Tubes Having Different Aspect Ratios,” Int. J. Refrig., 38(1), pp. 236–249. [CrossRef]
Darzi, M. , Akhavan-Behabadi, M. A. , Sadoughi, M. K. , and Razi, P. , 2015, “ Experimental Study of Horizontal Flattened Tubes Performance on Condensation of R600a Vapor,” Int. Commun. Heat Mass, 62, pp. 18–25. [CrossRef]
Nebuloni, S. , and Thome, J. R. , 2012, “ Numerical Modeling of the Conjugate Heat Transfer Problem for Annular Laminar Film Condensation in Microchannels,” ASME J. Heat Transfer, 134(5), p. 051021. [CrossRef]
Nebuloni, S. , and Thome, J. R. , 2010, “ Numerical Modeling of Laminar Annular Film Condensation for Different Channel Shapes,” Int. J. Heat Mass Transfer, 53(13–14), pp. 2615–2627. [CrossRef]
Nebuloni, S. , and Thome, J. R. , 2013, “ Numerical Modeling of the Effects of Oil on Annular Laminar Film Condensation in Minichannels,” Int. J. Refrig., 36(5), pp. 1545–1556. [CrossRef]
Brackbill, J. U. , Kothe, D. B. , and Zemach, C. , 1992, “ A Continuum Method for Modeling Surface-Tension,” J. Comput. Phys., 100(2), pp. 335–354. [CrossRef]
Yang, Z. , Peng, X. , and Ye, P. , 2008, “ Numerical and Experimental Investigation of Two Phase Flow During Boiling in a Coiled Tube,” Int. J. Heat Mass Transfer, 51(5), pp. 1003–1016. [CrossRef]
Wei, J. , Pan, L. , Chen, D. , Zhang, H. , Xu, J. , and Huang, Y. , 2011, “ Numerical Simulation of Bubble Behaviors in Subcooled Flow Boiling Under Swing Motion,” Nucl. Eng. Des., 241(8), pp. 2898–2908. [CrossRef]
Menter, F. R. , 1994, “ 2-Equation Eddy-Viscosity Turbulence Models for Engineering Applications,” AIAA J., 32(8), pp. 1598–1605. [CrossRef]
Rouhani, S. Z. , and Axelsson, E. , 1970, “ Calculation of Void Volume Fraction in Subcooled and Quality Boiling Regions,” Int. J. Heat Mass Transfer, 13(2), pp. 383–393. [CrossRef]
Kattan, N. , Thome, J. R. , and Favrat, D. , 1998, “ Flow Boiling in Horizontal Tubes—Part 2: New Heat Transfer Data for Five Refrigerants,” ASME J. Heat Transfer, 120(1), pp. 148–155. [CrossRef]
Thome, J. R. , El Hajal, J. , and Cavallini, A. , 2003, “ Condensation in Horizontal Tubes—Part 2: New Heat Transfer Model Based on Flow Regimes,” Int. J. Heat Mass Transfer, 46(18), pp. 3365–3387. [CrossRef]

Figures

Grahic Jump Location
Fig. 1

Computational geometry and boundary conditions

Grahic Jump Location
Fig. 2

Comparison between numerical void fraction and calculated values from models

Grahic Jump Location
Fig. 3

Comparison with experimental results at x = 0.45

Grahic Jump Location
Fig. 4

Comparison of numerical data with values computed from empirical correlations for heat transfer coefficients in round tubes at G ranging from 305 kg m−2 s−1 to1061 kg m−2 s−1 and x ranging from 0.41 to 0.98

Grahic Jump Location
Fig. 5

Local heat transfer coefficients versus vapor quality for round and flattened tubes with G = 421, 738, and 1061 kg m−2 s−1, and Tsat = 320 K

Grahic Jump Location
Fig. 6

Comparison of numerical heat transfer coefficients with values from empirical correlations using de and dh: (a) Cavallini et al. correlation [6] and (b) Thome et al. correlation [39].

Grahic Jump Location
Fig. 7

Liquid–vapor interfaces for R410A inside round and flattened tubes with G = 421 and 1061 kg m−2 s−1: (a) round tube, (b) AR = 3.07, (c) AR = 4.23, and (d) AR = 5.39

Grahic Jump Location
Fig. 8

The liquid film thickness along the axis direction inside flattened tubes when G = 421 and 1061 kg m−2 s−1: (a) G = 421 kg m−2 s−1, x = 0.5 and (b) G = 1061 kg m−2 s−1, x = 0.9

Grahic Jump Location
Fig. 9

The liquid film thicknesses as a function of the angular coordinate for R410A inside round and flattened tubes when: (a) G = 1061 kg m−2 s1, x = 0.9 and (b) G = 421 kg m−2 s−1, x = 0.5

Grahic Jump Location
Fig. 10

The local heat transfer coefficients against the angular coordinate with R410A when (a) G = 1061 kg m−2 s−1, x = 0.9 and (b) G = 421 kg m−2 s−1, x = 0.5

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In