• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.11
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• pp.1542-1547
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• 2003

Although dielectric barrier discharge (DBD) in air has been applied to a wider range of aftertreatment processes for HAPs (Hazardous Air Pollutants), due to its high electron density and energy, its potential use as precharging dust particles is not well known. In this work, we measured size distributions of bimodal aerosol particles and estimated collection efficiency of the particles by an electrostatic precipitator (ESP) using DBD as particle charger. To examine the particle collection with DBD charger, nano size particles of NaCl(20∼100nm) and DOS (50∼500nm) were generated by a tube furnace and an atomizer, respectively. For experimental conditions of 60㎐, 11㎸ and 60 lpm, the particle collection efficiency for the hybrid system was over 85%, based on the number of particles captured.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1272-1275
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• 2008

We present the development of dry etch process for the liquid crystal display (LCD) fabrication using a dielectric barrier discharge (DBD) system at atmospheric pressure. In this experimental work, the dry etch characteristics and the electrical properties of thin film transistor are evaluated by using the scanning electron microscopy and electric probe, and TFT-LCD panel ($300\;mm\;{\times}\;400\;mm$) is manufactured with the application of the amorphous silicon etch step in the 4 mask and 5 mask processes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.24 no.1
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• pp.57-63
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• 2011

Dielectric Barrier Discharge (DBD) reactor with sinsodual AC type of power supply is very widely adopted for its compact size and effective discharging mechanism to generate high density of ozone radicals. However, at the aspect of design on power supply, its optimal switching conditions and topology is achieved by empirical test. Therefore, throughout this paper, it is proposed a design method of DBD power supply to guarantee a maximum ozone yield rate in accordance with DBD reactor modification and impedance variation when rapid gas discharging in the DBD reactor is proceeded.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1435-1440
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• 2003

Although Dielectric Barrier Discharge (DBD) in air has been applied to a wider range of aftertreatment processes for HAPs(Hazardous Air Pollutants), due to its high electron density and energy, its potential use as precharging dust particles is not well known. In this work, we measured size distributions of bimodal aerosol particles and estimated collection efficiency of the particles by electrostatic precipitator(ESP) using DBD as particle charger. To examine the particle collection with DBD charger, nano size particles of NaCl($20{\sim}100$ nm) and DOS($50{\sim}800$ nm) were generated by tube furnace and atomizer, respectively. For experimental conditions of 60 Hz, 11 kV, and 60 lpm, the particle collection efficiency for the hybrid system comprising DBD charger and ESP was over 85 %, based on the number of particles captured.

• Journal of the Korean Society of Industry Convergence
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• v.6 no.4
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• pp.277-289
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• 2003

This study proposes a mathematical model to characterize the removal of nitrogen oxides in a dielectric barrier discharge plasma process. As well as the reactions between nitrogen oxides, water vapor, oxygen and nitrogen, the model takes into account the effect of ethylene often used as a chemical additive to reduce the power consumption of the process on the removal of nitrogen oxides. Since the concentrations of the radicals concerned in the main reactions including O, OH, H and N should be calculated to predict the removal efficiency of nitrogen oxides, they were theoretically derived. The parameters affecting the removal of nitrogen oxides, such as initial concentration, discharge power, humidity, and ethylene concentration were experimentally evaluated, which were compared with the calculated results to verify the validity of the model proposed. The predicted concentrations of several byproducts formed in this process were also presented and discussed. The effects of several parameters mentioned above on the removal of nitrogen oxides were reasonable described by the proposed model.

• Proceedings of the KIEE Conference
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• 1996.07c
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• pp.1816-1818
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• 1996

A micro-size nonthermal plasma generator, using a $SiO_2$ film as a dielectric barrier, has been studied experimentally for a high frequency ac voltage in 2LPM oxygen gas fed. The $SiO_2$ film as a micro-size dielectric barrier was made by the wet oxidation of n-type Si wafer($220[{\mu}mt]$). It can be generated ozone, as a nonthermal plasma intensity parameter, at very low level of applied voltage about 1[kV] by using the micro-size dielectric barrier. As a result, in case that have no air gap spacing i.e. surface discharge case shows relatively higher ozone concentration rather than that case of the micro-airgap spacing.

• 한국연소학회:학술대회논문집
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• 2003.12a
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• pp.27-32
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• 2003

The effect of non-thermal plasma on diffusion flames in co-flow jets has been studied experimentally by adopting a dielectric barrier discharge technique. The generation of streamers was enhanced with a flame due to increased reduced electric fields by high temperature burnt gas and the abundance of ions in the flame region. The effect of streamers on flame behavior reveals that the flame length was significantly decreased as the applied voltage increased and the yellow luminosity by the radiation of soot particles was also significantly reduced. The formation of PAH and soot was influenced appreciably by the non-thermal plasma, while the flame temperature and the concentration of major species were not influence much with the plasma generation. The results demonstrated that the application of non-thermal plasma can be a viable technique in controlling soot generation in flames with low power consumption in the order of 1 W.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.458-458
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• 2012

Fuel Cell is used stacking metal or polymer substrate. This hydro property of substrate surface is very important. Usually, surface property is hydrophilic. The surface oxidation of SUS is investigated through plasma treatments with an atmospheric-pressure dielectric barrier discharge (DBD) for increasing hydrophilic property. The plasma process makes an experiment under various operating conditions of the DBD, which operating conditions are treatment time, plasma gas mixture ratio, the plasma source supply frequency. Two kinds of SUS substrate, SUS-304 and SUS 316L, were used. Discharge frequency has a crucial impact on equipment performance and gas treatment. After the plasma treatment of a SUS plate, highly improved wettability was noted. But, when high oxygen supply, the substrate damaged seriously.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.1
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• pp.115-120
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• 2004

An indoor air cleaner consisting of a dielectric barrier discharge system and an electrostatic precipitator (ESP) was experimentally investigated. The function of the dielectric barrier discharge is to precharge particles by producing nonthermal plasma before indoor air enters ESP, leading to an enhancement in dust collection efficiency. The dependence of particle size distribution on the plasma discharge was examined to understand the mechanism of the particle precharging. The plasma discharge was found to increase the electrical force of the particles, rather than agglomerate them. Coarse particles in the range of 0.5 to $5.0{\mu}m$ were observed to be easily collected by this indoor air cleaner, and the present study laid emphasis on the removal of fine particles of $0.3{\mu}m$. The collection efficiency of the fine particles was largely enhanced by the plasma discharge.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.2
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• pp.157-165
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• 2003

A combined process of non-thermal plasma and catalytic technique has been investigated to treat $CH_3$CN gas in the atmosphere. A planar type dielectric barrier discharge (DBD) reactor has been used to generate the non-thermal plasma that produces various chemically active species, such as O, N, OH, $O_3$, ion, electrons, etc. Several different types of the beads. which are Molecular Sieve (MS) 5A, MS 13X, Pt/alumina beads, are packed into the DBD reactor, and have been tested to characterize the effects of adsorption and catalytic process on treating the $CH_3$CN gas in the DBD reactor. The test results showed that the operating power consumption and the amounts of the by-products of the non-thermal plasma process can be reduced by the assistance of the adsorption and catalytic process.