Effects of electrode arrangement on the combined hot-air flow and electric field drying
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Abstract
This research experimentally investigates the effects of electrode arrangement on the efficiency of a drying process utilizing hot-air flow and electric fields. Parameters are the number of electrodes (n = 1, 3, and 4 poles), and the distance between electrode and ground wires (L = 2 - 8 cm). High electrical voltage used for generating Corona wind is employed at 15 kV. Temperature and bulk mean velocity of hot-air flow are controlled at 60OC and 0.35 m/s, respectively. A porous medium is composed of water, air and glass beads of 0.125 mm in diameter. The results show that an increase of the number of electrodes affects the characteristics of circulating hot-air streams greatly. Moreover, it increases the drying rate substantially. When distance L becomes smaller, the size of Corona wind is smaller but the circulating flow is stronger. Consequently, the rates of heat and mass transfer in the porous medium are considerably enhanced.
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References
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