Numerical Study of Pure Electroconvection and Combined Electro-thermo-convection in Horizontal Channels

Authors

Unit of Metrology and Energy Systems, Department of Energetic, University of Monastir, Monastir, Tunisia

Abstract

Electrohydrodynamic effect on natural convection in horizontal channels is investigated from a numerical point of view. The EHD effect is induced by narrow strip electrodes placed at the bottom wall of the channel. The channel is subjected in a first stage only to the electric forces, and in a second stage to the simultaneous action of a temperature gradient and an electric field. The interactions between electric field, flow field and temperature field are analyzed. It can be concluded that charge density distribution, flow pattern and temperature distribution are substantially affected by the arrangement of the electrodes; in fact four different arrangement were treated. The effect of pure electroconvection on charge density distribution and on flow pattern was studied. A periodic flow corresponding to particular values of electric Rayleigh was observed, then the impact of combined electro-thermo convection on heat transfer was undertaken in a second step and it was noted that the optimum arrangement  of the electrodes provides an increase in heat transfer of up to 13%. The effect of the applied electric forces is also studied in order to highlight the importance of putting compromise between the supplied voltage and arrangement of the electrodes. Finally, a study of optimized configuration of electrodes was achieved.

Keywords

References

1.     Seyed-Yagoobi, J., "Electrohydrodynamic pumping of dielectric liquids", Journal of Electrostatics,  Vol. 63, No. 6, (2005), 861-869.
2.     Atten, P. and Seyed-Yagoobi, J., "Electrohydrodynamically induced dielectric liquid flow through pure conduction in point/plane geometry", IEEE Transactions on Dielectrics and Electrical Insulation,  Vol. 10, No. 1, (2003), 27-36.
3.     Hanaoka, R., Takata, S., Murakumo, M. and Anzai, H., "Properties of liquid jet induced by electrohydrodynamic pumping in dielectric liquids", Electrical Engineering in Japan,  Vol. 138, No. 4, (2002), 1-9.
4.     Yabe, A., Mori, Y. and Hijikata, K., "Ehd study of the corona wind between wire and plate electrodes", AIAA Journal,  Vol. 16, No. 4, (1978), 340-345.
5.     Velkoff, H. and Godfrey, R., "Low-velocity heat transfer to a flat plate in the presence of a corona discharge in air", Journal of Heat Transfer,  Vol. 101, (1979), 157-163.
6.     Yamamoto, T. and Velkoff, H., "Electrohydrodynamics in an electrostatic precipitator", Journal of Fluid Mechanics,  Vol. 108, (1981), 1-18.
7.     Tada, Y., Takimoto, A. and Hayashi, Y., "Heat transfer enhancement in a convective field by applying ionic wind", Journal of Enhanced Heat Transfer,  Vol. 4, No. 2, (1997), 140-149.
8.     Kasayapanand, N. and Kiatsiriroat, T., "Numerical modeling of the electrohydrodynamic effect to natural convection in vertical channels", International Communications in Heat and Mass Transfer,  Vol. 34, No. 2, (2007), 162-175.
9.     Yan, Y., Zhang, H. and Hull, J., "Numerical modeling of electrohydrodynamic (ehd) effect on natural convection in an enclosure", Numerical Heat Transfer, Part A: Applications,  Vol. 46, No. 5, (2004), 453-471.
10.   Sheikhzadeh, G., Arefmanesh, A., Kheirkhah, M. and Abdollahi, R., "Numerical study of natural convection in an inclined cavity with partially active side walls filled with cu-water nanofluid", International Journal of Engineering-Transactions B: Applications,  Vol. 24, No. 3, (2011), 279-288.
11.   Saha, G., Saha, S., Hasan, M. and Islam, M.Q., "Natural convection heat transfer within octagonal enclosure", IJE Transactions A: Basics,  Vol. 23, No. 1, (2010), 1-10.
12.   Maatki, C., Ghachem, K., Kolsi, L., Borjini, M. and Ben Aissia, H., "Entropy generation of double diffusive natural convection in a three dimensional differentially heated enclosure", International Journal of Engineering,  Vol. 2, (2014), 215-226.
13.   Aung, W., "Fully developed laminar free convection between vertical plates heated asymmetrically", International Journal of Heat and Mass Transfer,  Vol. 15, No. 8, (1972), 1577-1580.
14.   Bahrami, P. and Sparrow, E., "Experiments on natural convection from vertical parallel plates with either open or closed edges", Journal of Heat Transfer,  Vol. 102, (1980), 221-227.
15.   Morrone, B., Campo, A. and Manca, O., "Optimum plate separation in vertical parallelplate channels for natural convective flows: Incorporation of large spaces at the channel extremes", International Journal of Heat and Mass Transfer,  Vol. 40, No. 5, (1997), 993-1000.
16.   Lee, K.-T., "Natural convection heat and mass transfer in partially heated vertical parallel plates", International Journal of Heat and Mass Transfer,  Vol. 42, No. 23, (1999), 4417-4425.
17.   Kasayapanand, N., "Enhanced heat transfer in inclined solar chimneys by electrohydrodynamic technique", Renewable Energy,  Vol. 33, No. 3, (2008), 444-453.
18.   Hassen, W., Traore, P., Borjinia, M. and Aissiaa, H.B., "Numerical study of electro-thermo-convection in a differentially heated cavity filled with a dielectric liquid subjected to partial unipolar injection", International Journal of Engineering-Transactions C: Aspects,  Vol. 28, No. 9, (2015), 1343-1350.
19.   Hassen, W., Elkhazen, M.I., Traore, P. and Borjini, M.N., "Numerical study of the electro–thermo-convection in an annular dielectric layer subjected to a partial unipolar injection", International Journal of Heat and Fluid Flow,  Vol. 50, (2014), 201-208.
20.   Lakeh, R.B. and Molki, M., "Enhancement of convective heat transfer by electrically-induced swirling effect in laminar and fully-developed internal flows", Journal of Electrostatics,  Vol. 71, No. 6, (2013), 1086-1099.
21.   Moghanlou, F.S., Khorrami, A.S., Esmaeilzadeh, E. and Aminfar, H., "Experimental study on electrohydrodynamically induced heat transfer enhancement in a minichannel", Experimental Thermal and Fluid Science,  Vol. 59, (2014), 24-31.
22.   Nasirivatan, S., Kasaeian, A., Ghalamchi, M. and Ghalamchi, M., "Performance optimization of solar chimney power plant using electric/corona wind", Journal of Electrostatics,  Vol. 78, No., (2015), 22-30.
23.   Kasayapanand, N., "Electrode arrangement effect on natural convection", Energy conversion and management,  Vol. 48, No. 4, (2007), 1323-1330.
24.   Peng, M., Wang, T.-H. and Wang, X.-D., "Effect of longitudinal electrode arrangement on ehd-induced heat transfer enhancement in a rectangular channel", International Journal of Heat and Mass Transfer,  Vol. 93, (2016), 1072-1081.
25.   Hassen, W., Borjini, M., Traore, P. and Aissia, H.B., "Electroconvection between coaxial cylinders of arbitrary ratio subjected to strong unipolar injection", Journal of Electrostatics,  Vol. 71, No. 5, (2013), 882-891.
26.   Atten, P. and Moreau, R., "Stabilite electrohydrodynamique des liquides isolants soumis a une injection unipolaire", Journal of Mecanique,  Vol. 11, No. 3, (1972), 471-521.
27.   Atten, P. and Lacroix, J., "Non-linear hydrodynamic stability of liquids subjected to unipolar injection", Journal de Mécanique,  Vol. 18, (1979), 469-510.
28.   El Moctar, A.O., Peerhossaini, H., Le Peurian, P. and Bardon, J., "Ohmic heating of complex fluids", International Journal of Heat and Mass Transfer,  Vol. 36, No. 12, (1993), 3143-3152.
29.   Patankar, S., "Numerical heat transfer and fluid flow", CRC press,  (1980), ISBN: 9780891165224.
30.   Borjini, M.N., Abidi, A. and Aissia, H.B., "Prediction of unsteady natural convection within a horizontal narrow annular space using the control-volume method", Numerical Heat Transfer, Part A: Applications,  Vol. 48, No. 8, (2005), 811-829.
31.   Bejan, A., "Convection heat transfer", John wiley & sons,  (2013), ISBN: 9781118671627.
32.   Vazquez, P., Georghiou, G. and Castellanos, A., "Numerical analysis of the stability of the electrohydrodynamic (ehd) electroconvection between two plates", Journal of Physics D: Applied Physics,  Vol. 41, No. 17, (2008), 175303-175310.
International Journal of Engineering
Volume 30, Issue 8
TRANSACTIONS B: Applications
August 2017
Pages 1270-1278

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