The effect of an electric field on the falling-film evaporation of refrigerant R-134a on a vertical plate and three commercially available tubes was investigated experimentally. The plate test section was 25.4 mm wide and 76.2 mm long, and each tube test section was 19 mm in diameter and 140 mm long. Experiments were conducted in both falling film and spray evaporation modes. The effects of various parameters such as heat flux, refrigerant flow rate, electrode gap, and applied voltage were investigated. It was found that in the presence of an applied electric field, the maximum enhancement in the heat transfer coefficient for both falling film and spray evaporation modes on a plate was nearly the same. A maximum enhancement of fourfold in the heat transfer coefficient with the plate, 90 percent with the smooth tube, 110 percent with the Turbo BIII, and 30 percent with 19 fpi tube were obtained. The electrohydrodynamic power consumption in all cases was less than 0.12 percent of the total energy exchange rate in the test section. [S0022-1481(00)03003-6]

Issue Section:
Phase Change and Multiphase Heat Transfer
Keywords:
liquid films, sprays, evaporation, electrohydrodynamics, organic compounds, heat transfer, Augmentation, Electric Fields, Enhancement, Film, Heat Transfer, Thin Films
Topics:
Electric fields, Electrodes, Evaporation, Flow (Dynamics), Heat flux, Heat transfer, Heat transfer coefficients, Refrigerants, Sprays, Heat, Turbochargers, Electrohydrodynamics, Energy consumption
1.
Minton, P. E., 1986, Handbook of Evaporation Technology, Noyes Publications, Park Ridge, NJ.
2.
Bochirol
,
L.
,
Bonjour
,
E.
, and
Weil
,
L.
,
1960
, A Echanges thermiques “
Etude de l’Action de Champs Electriques sur les Transferts de Chaleur dans les Liquides Bouillants
,”
C. R. Hebd. Seances Acad. Sci., Paris
250
, pp.
76
–
78
.
3.
Choi, H. Y., 1962, “Electrohydrodynamic Boiling Heat Transfer,” Ph.D. thesis, Massachusetts Institute of Technology, Cambridge, MA.
4.
Winer, M., 1967, “An Experimental Study of the Influence of Nonuniform Electric Field on Heat Transfer in a Dielectric Fluid,” TRW Systems Report, Report No. EM17-14.
5.
Zhorzholiani
,
A. G.
, and
Shekriladze
,
I. G.
,
1972
, “
Study of the Effect of an Electrostatic Field on Heat Transfer With Boiling Dielectric Fluids
,”
Heat Transfer-Sov. Res.
,
4
, No.
4
, pp.
81
–
98
.
6.
Jones
,
T. B.
,
1978
, “
Electrohydrodynamically Enhanced Heat Transfer in Liquids—A Review
,”
Adv. Heat Transfer
,
14
, pp.
107
–
148
.
7.
Ohadi
,
M. M.
,
1991
, “
Heat Transfer Enhancement in Heat Exchangers
,”
ASHRAE J.
,
3
, No.
12
, pp.
42
–
50
.
8.
Yabe, A., 1991, “Active Heat Transfer Enhancement by Applying Electric Fields,” Proceedings of the Third ASME/JSME Thermal Engineering Conference, Vol. 3, ASME, New York, pp. xv–xxiii.
9.
Panofsky, W. K. H., and Phillips, M., 1962. Classical Electricity and Magnetism, Addison-Wesley, Reading, MA, p. 110.
10.
Kline
,
S. J.
, and
McClinock
,
F. A.
,
1953
, “
Describing Uncertainties in Single Sample Experiments
,”
Mech. Eng. (Am. Soc. Mech. Eng.)
,
75
, No.
1
, pp.
3
–
8
.
11.
Moffat
,
R. J.
,
1988
, “
Describing the Uncertainties in Experimental Results
,”
ASME J. Fluids Eng.
,
107
, pp.
250
–
260
.
12.
Yamashita
,
K.
, and
Yabe
,
A.
,
1997
, “
Electrohydrodynamic Enhancement of Falling Film Evaporation Heat Transfer and its Long Term Effect on Heat Exchanger
,”
ASME J. Heat Transfer
,
119
, pp.
339
–
347
.
13.
Darabi J., Ohadi, M. M., and Dessiatoun, S. V., 1998, “Heat Transfer Enhancement With Falling Film Evaporation on Vertical Tubes Using Electric Fields,” Proceedings of the ASME Heat Transfer Division, Vol. 1, ASME, New York, pp. 331–38.
Copyright © 2000
 by ASME
You do not currently have access to this content.