Study on the Characteristics and Heat Dissipation Effect of Ionic Wind Generated by Multi-Needle Net Electrode in Corona Discharge*

Abstract A thin, flexible plate electrode was adopted to generate both ionic wind and vibration in our previous study. The design contains a metal inductor placed next to the plate electrode so that it is attracted to vibrate by the induced electrostatic force. The resulting flow was used to enhance heat transfer. In this study, a numerical methodology is developed to unveil the flow structure induced by the corona discharge and electrode vibration. The oscillatory movement of the electrode is modeled as a cantilever beam vibrating at its first resonant mode. The electric and flow fields are solved by the finite volume methods. It is shown that a jet-like flow is generated by the electric discharge. The oscillatory movement of the jet results in flat temperature profile in comparison with the corona only system. Owing to the unsteady characteristic, the jet strength is less strong than that without vibration. The calculated results are qualitatively in line with the experiments, though some considerable differences exist. It is found that the oscillatory flow brings about lower overall heat transfer effectiveness than that without vibration regardless of the corona voltage. On the contrary, experiments showed that heat transfer is enhanced at low corona voltages where the ionic wind is not so overwhelming. The disagreement is mainly attributed to the 2-D assumption made in the simulation. The experimental arrangement, the corona discharge, and the vortex flows resulted all are three-dimensional. Therefore, 3-D calculations become necessary.

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A review on recent advances and challenges of ionic wind produced by corona discharges with practical applications

Journal of Physics D Applied Physics ◽

10.1088/1361-6463/ac3e2c ◽

2021 ◽

Author(s):

Jingguo Qu ◽

Minjun Zeng ◽

Dewei Zhang ◽

Dakai Yang ◽

Xiongwei Wu ◽

...

Keyword(s):

Corona Discharge ◽

Experimental Studies ◽

Wind Generation ◽

Future Research ◽

Discharge Process ◽

Ionic Wind ◽

Practical Applications ◽

Wind Generators ◽

Wide Range ◽

Gas Ionization

Abstract Ionic wind, an induced phenomenon during corona discharge, possessing the features of silent operation and no moving parts, has a wide range of applications. Ionic wind generation is accompanied by complex physical processes, involving gas ionization, ion recombination, flow, and various chemical reactions, as well as mutual couplings between some of them. Therefore, understanding the corona discharge process and ionic wind generation is crucial for researchers and engineers to better utilize this phenomenon in practical applications. In this review, the principles of corona discharge and its induced ionic wind are presented. Subsequently, ionic wind generators (IWGs) are discussed according to their applications, and the corresponding advances based on experimental studies and numerical simulations are also reviewed. Moreover, the challenges of transitioning the ionic wind technology from laboratory studies to practical applications are discussed. These challenges include the excessively high onset voltage of the corona, ozone emission, and influence of environmental conditions. Furthermore, the mechanisms of these barriers and several effective approaches for mitigating them are provided. Finally, some future research prospects and the conclusions are presented.

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Simulation of Ferrofluid Heat Dissipation Effect on Natural Convection at an Inclined Cavity Filled with Kerosene/Cobalt Utilizing the Lattice Boltzmann Method

Numerical Heat Transfer Part A Applications ◽

10.1080/10407782.2013.836022 ◽

2013 ◽

Vol 65 (6) ◽

pp. 509-530 ◽

Cited By ~ 53

Author(s):

GH. R. Kefayati

Keyword(s):

Natural Convection ◽

Lattice Boltzmann Method ◽

Lattice Boltzmann ◽

Heat Dissipation ◽

Dissipation Effect ◽

Inclined Cavity ◽

Boltzmann Method

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An empirical model for ionic wind generation by a needle-to-cylinder dc corona discharge

Journal of Electrostatics ◽

10.1016/j.elstat.2014.11.001 ◽

2015 ◽

Vol 73 ◽

pp. 125-130 ◽

Cited By ~ 27

Author(s):

Longnan Li ◽

Seung Jun Lee ◽

Wonjung Kim ◽

Daejoong Kim

Keyword(s):

Corona Discharge ◽

Empirical Model ◽

Wind Generation ◽

Ionic Wind

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A Novel Means Combining Corona Discharge and Electrostatic Force-Induced Vibration for Convective Heat Transfer

Journal of Heat Transfer ◽

10.1115/1.4046971 ◽

2020 ◽

Author(s):

Yeng-Yung Tsui ◽

Ting-Kai Wei ◽

Chi-Chuan Wang

Keyword(s):

Heat Transfer ◽

Corona Discharge ◽

Cooling System ◽

Electrostatic Force ◽

Mechanical Vibration ◽

Periodic Oscillation ◽

Mechanical Effect ◽

Flexible Plate ◽

Ionic Wind ◽

Maximum Increase

Abstract A new design, not reported in the existing literature, combining features of ionic wind and mechanical vibration to induce appreciable airflow is developed. Its feasibility is demonstrated in a cooling system to enhance heat transfer. Ionic wind is generated via using a thin, flexible plate as the emitting electrode and a heated, vertical plate as the collecting electrode. By placing a metal inductor close to the discharge electrode, an electrostatic filed is formed. The electrode is attracted and thus moves towards the inductor owing to the electrostatic force created. To sustain periodic oscillation and produce large vibrational amplitudes, the inductor is grounded using current limiting resistors. Vibrational characteristics are highly dependent on the corona voltage, resistance of the resistor, and position of the induction plate, which are examined in the experiments. It was found that the heat transfer enhancement is not improved at high corona voltages because the ionic wind overwhelms the mechanical effect of vibration. The vibrational effect becomes more prominent at low corona voltages with which the electrical field created by the corona discharge is not so intense. The maximum increase of heat transfer coefficient over that without vibration can be as large as 13.4 % at the lowest corona voltage considered in the tests.

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