Heat transfer coefficients during evaporation in a horizontal smooth tube for R-22 and R-407C (R-32/125/134a, 23/25/52 wt.%) have been measured using thermochromic liquid crystal. Focus has been put on the circumferential variation of heat transfer coefficients at several cross-sections of the test tube with inner diameter of 11.3 mm for several vapor qualities of refrigerant. The inner wall temperatures were calculated by one dimensional heat conduction equation from the measured outer wall temperatures, which were obtained using an image processing technique with thermochromic liquid crystal (TLC). The relation between measured temperature and color information (Red-Green-Blue values) of thermochromic liquid crystal was calibrated by a neural network method. Results show that circumferential variation of heat transfer coefficients for R-22 is quite large with the highest heat transfer coefficient at the top of the tube. For zeotropic mixture of R-407C, similar trend has been observed with less difference between the heat transfer coefficients at the top and bottom than that of R-22.
Issue Section:
Evaporative Boiling and Condensation
1.
Wang
, C. C.
, Kuo
, C. S.
, Chang
, Y. J.
, and Lu
, D. C.
, 1996
, “Two-Phase Flow Heat Transfer and Friction Characteristics of R-22 and R-407C
,” ASHRAE Trans.
, 102
, Part 1, pp. 830
–838
.2.
Shin
, J. Y.
, Kim
, M. S.
, and Ro
, S. T.
, 1996
, “Correlation of Convective Boiling Heat Transfer in a Horizontal Tube for Pure Refrigerants and Refrigerant Mixtures
,” Korean Journal of Air-Conditioning and Refrigeration Engineering
, 8
(9
), pp. 254
–266
.3.
Kim
, S. H.
, Kwak
, K. M.
, Bai
, C. H.
, and Chung
, M.
, 1997
, “An Experimental Study on Nucleate Boiling of Ternary Refrigerant R407C
,” Korean Journal of Air-conditioning and Refrigeration Engineering
, 9
(3
), pp. 276
–283
.4.
Choi
, T. Y.
, Kim
, Y. J.
, Kim
, M. S.
, and Ro
, S. T.
, 2000
, “Evaporation Heat Transfer of R-32, R-134a, R-32/134a, and R-32/125/134a inside a Horizontal Smooth Tube
,” Int. J. Heat Mass Transf.
, 43
, pp. 3651
–3660
.5.
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
, pp. 148
–155
.6.
Gungor
, K. E.
, and Winterton
, R. H. S.
, 1987
, “Simplified General Correlation for Flow Saturated Boiling and Comparisons of Correlations with Data
,” Chem. Eng. Res. Des.
, 65
, pp. 148
–156
.7.
Jung
, D. S.
, McLinden
, M.
, Radermacher
, R.
, and Didion
, D.
, 1989
, “A Study of Flow Boiling Heat Transfer with Refrigerant Mixture
,” Int. J. Heat Mass Transf.
, 9
(1
), pp. 1751
–1764
.8.
Kandlikar
, S. G.
, 1990
, “A General Correlation for Saturated Two-phase Flow Boiling Heat Transfer Inside Horizontal and Vertical Tubes
,” ASME J. Heat Transfer
, 112
, pp. 219
–228
.9.
Kandlikar
, S. G.
, 1998
, “Boiling Heat Transfer with Binary Mixtures: Part II—Flow Boiling in Plain Tubes
,” ASME J. Heat Transfer
, 120
, pp. 388
–394
.10.
Kattan
, N.
, Thome
, J. R.
, and Favrat
, D.
, 1998
, “Flow Boiling in Horizontal Tubes: Part 3-Development of a New Heat Transfer Model Based on Flow Pattern
,” ASME J. Heat Transfer
, 120
, pp. 156
–165
.11.
Ross
, H.
, Radermacher
, R.
, and Di Marzo
, M.
, 1987
, “Horizontal Flow Boiling of Pure and Mixed Refrigerants
,” Int. J. Heat Mass Transf.
, 30
(5
), pp. 979
–992
.12.
Jung
, D. S.
, McLinden
, M.
, Radermacher
, R.
, and Didion
, D.
, 1989
, “Horizontal Flow Boiling Heat Transfer Experiments with a Mixture of R22/R114
,” Int. J. Heat Mass Transf.
, 32
, pp. 131
–145
.13.
Yoshida, S., Mori, H., Matsunaga, T., and Ohishi, K., 1991, “Heat Transfer to Non-Azeotropic Mixtures of Refrigerants Flowing in a Horizontal Evaporator Tube,” ASME/JSME Thermal Eng. Proc., 2, pp. 295–300.
14.
Niederkru¨ger
, M.
, Steiner
, D.
, and Schlu¨nder
, E.-U.
, 1992
, “Horizontal Flow Boiling Experiments of Saturated Pure Components and Mixtures of R846-R12 at High Pressures
,” Int. J. Refrig.
, 15
(1
), pp. 48
–58
.15.
Boyd
, R. D.
, Smith
, A.
, and Turknett
, J.
, 1995
, “Two-Dimensional Wall Temperature Measurements and Heat Transfer Enhancement for Top-Heated Horizontal Channels With Flow Boiling
,” Exp. Therm. Fluid Sci.
, 11
, pp. 372
–386
.16.
Shin
, J. Y.
, Kim
, M. S.
, and Ro
, S. T.
, 1997
, “Experimental Study on Forced Convective Boiling Heat Transfer of Pure Refrigerants and Refrigerant Mixtures in a Horizontal Tube
,” Int. J. Refrig.
, 20
, pp. 267
–275
.17.
Camci
, C.
, Kim
, K.
, Hippensteele
, S. A.
, and Poinsatte
, P. E.
, 1993
, “Evaluation of a Hue Capturing Based Transient Liquid Crystal Method for High-Resolution Mapping of Convective Heat Transfer on Curved Surfaces
,” ASME J. Heat Transfer
, 115
, pp. 311
–318
.18.
Matsumoto
, R.
, Kikkawa
, S.
, and Senda
, M.
, 1997
, “Effect of Pin Fin Arrangement on Endwall Heat Transfer
,” JSME Int. Journal, Series B
, 40
(1
), pp. 142
–151
.19.
Kimura
, I.
, Kuroe
, Y.
, and Ozawa
, M.
, 1993
, “Application of Neural Networks to Quantitative Flow Visualization
,” J. Flow Visualization and Image Processing
, 1
, pp. 261
261
.20.
Huber, M., Gallagher, J., McLinden, M., and Morrison, G., 1996, NIST Thermodynamic Properties of Refrigerants and Refrigerant Mixtures Database (REFPROP) Version 5.0, National Institute of Standards and Technology, U.S.A.
21.
Dittus, F. W., and Boelter, L. M. K., 1930, University of California (Berkeley) Publications of Engineering, 2, University of California, Berkeley, CA, pp. 443.
22.
Thome
, J. R.
, and Shakir
, S.
, 1987
, “A New Correlation for Nucleate Pool Boiling of Aqueous Mixtures
,” AIChE Symp. Ser.
, 83
(257
), pp. 46
–51
.Copyright © 2002
by ASME
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