The present study investigates the possible drying enhancement provided by auxiliary heating to the sample in addition to the application of electric field. The electric field is produced by charging a needle electrode with direct current at a sufficiently high voltage. The auxiliary heating is provided through a thermofoil heater attached to the bottom plate of the sample container. The samples used are 3 mm and 6 mm glass beads saturated with water. Both positive and negative corona discharges have been employed. Two sets of experiments have been conducted, with and without cross-flow, at 1 kV increment from the corona threshold voltage until the occurrence of sparkover. For each case, a companion experiment was carried out simultaneously under the same ambient conditions but without the application of electric field or auxiliary heating. The result of which is used as a basis in the evaluation of drying enhancement using electric field (with or without cross-flow). The drying enhancement is evaluated as a function of the governing electric field parameters. In addition, the performance of EHD drying is compared with the conventional drying techniques.

Issue Section:
Technical Papers
Keywords:
drying, electric field effects, electric heating, electrohydrodynamics, corona, glass
Topics:
Drying, Electric fields, Heating, Cross-flow, Glass beads, Corona discharge
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