Electrohydrodynamic and heat transfer characteristics of a planar ionic wind generator with flat electrodes

Abstract

• Two corona discharges with different polarities are produced simultaneously. • The minimum discharge gap to maintain a stable corona discharge is determined. • The intensity and direction of the generated ionic wind is revealed. • The relationship between the heat transfer enhancement ratio and power consumption is established. In this study, a planar ionic wind generator with two flat electrodes was investigated numerically and experimentally to reveal its electrohydrodynamic and heat transfer characteristics. The multi-physical characteristics, including the discharge process, movement of electrons, positive ions, and negative ions, as well as the formation of ionic wind and its flow characteristics were simulated numerically. It was found that two corona discharges with different polarities were produced simultaneously when a high voltage was applied between the emitting and the ground electrodes. The intensity and direction of ionic wind produced by planar ionic wind generator was revealed. The effects of discharge gap, flat electrode thickness, and discharge polarity on the heat transfer characteristics and power consumption of the planar ionic wind generator were also investigated experimentally. The minimum discharge gap to maintain a stable corona discharge is determined. A better heat dissipation capacity of the planar ionic wind generator can be obtained with a larger electrode gap, and the optimized ionic wind generator can reduce the surface temperature of a 2.05 W powered heat source by more than 46 °C compared with natural cooling. The maximum heat transfer coefficient is 35 W∙m −2 ∙K −1 . This study can provide a theoretical guidance for the application of planar ionic wind generators to highly compact electronic devices.