Investigation of Corona wind Effect on Heat and Mass Transfer Enhancement
Commenced in January 2007
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Edition: International
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Investigation of Corona wind Effect on Heat and Mass Transfer Enhancement

Authors: R.Karami, B.Kamkari, K.Kashefi

Abstract:

Applying corona wind as a novel technique can lead to a great level of heat and mass transfer augmentation by using very small amount of energy. Enhancement of forced flow evaporation rate by applying electric field (corona wind) has been experimentally evaluated in this study. Corona wind produced by a fine wire electrode which is charged with positive high DC voltage impinges to water surface and leads to evaporation enhancement by disturbing the saturated air layer over water surface. The study was focused on the effect of corona wind velocity, electrode spacing and air flow velocity on the level of evaporation enhancement. Two sets of experiments, i.e. with and without electric field, have been conducted. Data obtained from the first experiment were used as reference for evaluation of evaporation enhancement at the presence of electric field. Applied voltages ranged from corona threshold voltage to spark over voltage at 1 kV increments. The results showed that corona wind has great enhancement effect on water evaporation rate, but its effectiveness gradually diminishes by increasing air flow velocity. Maximum enhancements were 7.3 and 3.6 for air velocities of 0.125 and 1.75 m/s, respectively.

Keywords: Electrohydodynamics (EHD), corona wind, high electric field, Evaporation enhancement

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1334429

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References:


[1] Laohalertdechaa, S., Naphonb, P., Wongwises, S., "A review of electrohydrodynamic enhancement of heat transfer", Renewable and Sustainable Energy Review, Vol. 11, pp. 858-876, 2007.
[2] Molki, M., Bhamidipati, K., "Enhancement of convective heat transfer in the developing region of circular tubes using corona wind", International Journal of Heat and Mass Transfer, Vol. 47, pp. 4301-4314, 2004.
[3] Sadek, H., Robinson, A.J., Cotton, J.S., Ching, C.Y., Shoukri, M., "Electrohydrodynamic enhancement of in-tube convective condensation heat transfer", International Journal of Heat and Mass Transfer, Vol. 49, pp. 1647-1657, 2006
[4] Alemrajabi, A., Lai, F. C., "EHD-enhanced drying of partially wetted glass beads", Drying Technology, Vol. 23, pp. 597-60923, 2005.
[5] Goodenough T.I.J., Goodenough P.W, Goodenough S.M. "The efficiency of corona wind drying and its application to the food industry", Journal of food engineering, Vol. 80, pp. 1233-1238, 2007.
[6] Lai, F.C., Huang, M., Wong, D. S., "EHD-Enhanced Water Evaporation", Drying Technology, Vol. 22, pp. 595-606, 2004.
[7] Lai, F.C., Sharma, R.K., "EHD-enhanced drying with multiple needle electrode", Journal of Electrostatics, Vol. 63, pp. 223-237, 2005.
[8] Chen, Y.H., Barthakur, N.N., "Electrohydrodynamic drying of potato slabs", Journal of Food Engineering, Vol. 23, pp. 107-119, 1994.
[9] Barthakur, N.N., "Electrohydrodynamic enhancement of evaporation from Nacl solutions", Desalination, Vol. 78, pp. 455-465, 1990.
[10] Rashkovan, A., Sher, E., & Kalman, H. "Experimental optimization of an electric blower by corona wind", Applied Thermal Engineering, Vol. 22, 1587-1599, 2002.
[11] Stuetzer, M., "Ion Drag Presuure Generation", Journal of Applied Physics, Vol. 30, pp. 984-994, 1959.
[12] Kamkari, B. "Experimental Investigation of Water Evaporation Enhancement Using Electrohydro-dynamics", M.Sc. thesis, Department of Mechanical Engineering, Isfahan University of Technology, 2008.
[13] Sadek, S., Fax, E., Hurwitz, M.,"The influence of electric fields on convective heat and mass transfer from a horizontal surface under force convection", journal of heat transfer, Vol. 94, pp. 144-148, 1972.