An experimental study was performed to investigate the effect of an intermittent electric field on forst reduction on vertical flat plats. The experiments were carried out in humid air under natural convection. The frosting plate was subjected to the electric field via an insulated high-voltage electrode positioned parallel to the plate. The lectric body-force applied by the electric field on the frost crystals altered the crystal formation and partially removed the frost from the surface. Experiments started with interval timing of the high voltage applied to the electrode. The power supply was turned on the applied to the electrode. The power supply was turned on and off at predetermined time intervals. It was found that the electric charge buildup on the insulation coating of the electrode reduced the electric field intensity, leading to a loss of performance in effectively controlling crystal growth. The intermittent field, however, performed well and removed many crystals from the frosting surface, causing them to migrate towards the electrode. An optimum on/off cycle for the electric field was found. Using on/off interval timings of 10/1 to 29/1 minutes, frost reduction ranged from 34.7
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