• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1261-1266
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• 2004

Dielectric Barrier Discharge (DBD) in air, which has been established for the production of large quantities of ozone, is more recently being applied to a wider range of aftertreatment processes for HAPs (Hazardous Air Pollutants). Although DBD has high electron density and energy, its potential use as precharging nano and submicron particles are not well known. In this work, we measured I-V characteristics of DBD and estimated collection efficiency of the particles by DBD type 2-stage ESP. To examine the particle collection with various applied voltage waveforms of DBD for nano and submicron sized, bimodal particles were generated by a electrical tube furnace and an atomizer.

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권3호
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• pp.101-105
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• 2004

The efficient power MOSFET inverter applied for a simple and low cost power supply is proposed for driving the dielectric barrier discharge (DBD) lamp load. For decades, the DBD phenomenon has been used for ozone gas production in industry. In this research, the ultraviolet and visible light sources utilizing the DBD lamp is considered as the load for solid-state high frequency power supply. It is found that the simple voltage-source single-ended quasi-resonant ZVS inverter with only one active power switch could effectively drive this load with the output power up to 700 W. The pulse density modulation based control scheme for the single-ended quasi-resonant ZVS inverter using a low voltage and high current power MOSFET switching device is proposed to provide a linear power regulation characteristic in the wide range 0-100％ of the full power as compared with the conventional control based Royer type parallel resonant inverter type power supplies.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.527-528
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• 2012

플라즈마 유동제어를 통한 공기저항저감을 위해 DBD(Dielectric Barrier Discharge) 플라즈마 구동기를 설계하였고, 2D 시험모델의 풍동시험을 통해 항력저감을 측정하였다. 풍속이 없는 경우에는 유동박리 및 표면마찰저항이 존재하지 않으므로 플라즈마 유동제어를 통한 항력저감도 없었다. 2m/s의 풍속에서 유동박리제어를 통해 항력이 9.7%까지 감소됨을 확인하였으며, 풍속이 증가할수록 항력저감은 감소하였다.

• Korean Journal of Chemical Engineering
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• 제35권12호
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• pp.2452-2463
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• 2018

Surface treatment of sol-gel bioglass is required to increase its biomedical applications. In this study, a dielectric barrier discharge (DBD) plasma treatment in atmospheric pressure was performed on the surface of [$SiO_2-CaO-P_2O_5-B_2O_3$] sol-gel derived glass. The obtained bioglass was treated by plasma using discharge current 12 mA with an exposure period for 30 min. The type of discharge can be characterized by measuring the discharge current and applied potential waveform and the power dissipation. Apatite formation on the surface of the DBD-treated and untreated samples after soaking in simulated body fluid (SBF) at $37^{\circ}C$ is characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), inductively coupled plasma (ICP-OES) and scanning electron microscopy coupled with energy dispersive spectroscopy (SEM/EDS). We observed a marked increase in the amount of apatite deposited on the surface of the treated plasma samples than those of the untreated ones, indicating that DBD plasma treatment is an efficient method and capable of modifying the surface of glass beside effectively transforming it into highly bioactive materials.

• 한국환경과학회지
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• 제23권6호
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• pp.1165-1173
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• 2014

For the field application of dielectric barrier discharge plasma reactor in nutrient solution culture, a filtration-DBD (dielectric barrier discharge) plasma reactor was investigated for the Ralstonia solanacearum which causes bacterial wilt in aquiculture. The filtration-DBD plasma reactor system of this study was consisted of filter, plasma reactor, reservoir. The DBD plasma reactor consisted of a quartz dielectric tube, discharge electrode (inner) and ground electrode (outer). The experimental results showed that the inactivation of R. solanacearum with filter media type in filter reactor ranked in the following order: anthracite > fiber ball > sand > ceramic ball > quartz ceramic. In filtration + plasma process, disinfection effect with the voltage was found to small. In disinfection time of 120 minutes, residual R. solanacearum concentration was 1.17 log (15 CFU/mL). When the continuous disinfection time was 120 minute, disinfection effect was thought to keep the four days. In sporadic operation mode of 30 minutes disinfection - 24 hours break, residual R. solanacearum concentration after five days was 0.3 log (2 CFU/mL). It is considered that most of R. solanacearum has been inactivated substantially.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1556-1558
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• 1994

An air/quartz dielectric double barrier pulse discharge has been investigated to develop a novel si lent type ozone generator. It is found that there are very active pulsed coronas occurred in the airgap which are very useful for ozone generation. And, the corona onset voltage of the airgap of the air/quartz double barrier was enfluenced greatly by the airgap of the air/quartz dielectric double barrier, and depended greatly upon the airgap ranged of $0.0{\sim}3.0mm$ and by the quartz tube thickness ranged of $1.75{\sim}2.25mm$.

• 한국재료학회지
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• 제16권9호
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• pp.543-549
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• 2006

Polyimides (PI) are treated with $He/O_2$ and $He/O_2/NF_3$ atmospheric pressure rf dielectric barrier discharge in order to investigate the roles of $NF_3$ that is one of the PI etching gases. Surface changes are analyzed by x-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and contact angle measurement. The surface roughness of PI and the ratio of C=O, which is hydrophilic functional group, is more increased by $He/O_2/NF_3$ discharge than by $He/O_2$ discharge. The C=O species on the PI surface is increased up to 30 percent with rf power. The surface roughness of PI is increased from 0.4 to 11 nm with rf power. The water drop contact angles on PI, however, are reduced from $65^{\circ}\;to\;9^{\circ}$ by plasma treatment independently of $NF_3$.

• 조명전기설비학회논문지
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• 제28권1호
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• pp.114-122
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• 2014

This paper describes a study of the design conditions of a planar surface dielectric barrier discharge (DBD) reactors for generating negative air ions. The capacity of negative air ion generated by the surface DBD reactor is affected by the shape, area ratio and the location of the discharge and induction electrodes of it. To study the optimal design conditions of DBD reactors, the electrodes printed on the substrate of a PCB board is utilized to conduct kind of experiments: the distance of the each electrode along with the X-Y axis, the area ratio of the discharge electrode to induction electrode, and the symmetrical and asymmetrical location of two electrodes. The ion generation capacity is inverse proportional to the gap increases along with X-Y axis. And the optimum ion concentration generated by the ionizer was inspected when the electrodes area ratio was 3 and 5 times of the symmetrical and asymmetrical experimental condition respectively.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제48권5호
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• pp.385-390
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• 1999

Surface corona discharge characteristics of a dc corona charged ferroelectric pellet barrier have been investigated experimentally. Electric charges stored on the surfaces of the ferroelectric pellets by a dc corona discharge provide partial electric fields on the surfaces of the ferroelectric pellets, which could generate surface corona discharges on the ferroelectric pellets. This system utilizes both the surface discharges on the ferroelectric pellet barrier and the corona discharge between corona tip and mesh electrode. Positive and negative dc voltages were applied to the tip to generate partial discharges, and corona currents were estimated to investigate the buildup charge on ferroelectric pellets as a function of the applied time and the charge relaxation time constants of ferroelectric pellets. As a result, in the case of the negative corona discharge with the ferroelectric pellet barrier, the mean corona current and ozone generation increase greatly, and the surface discharges on the ferroelectric pellets can be fenerated efficiently. It is also found that, charge relaxation time, dielectric constants offerroelectric pellets, polarity of applied voltage and applied time affected to the surface discharges among the ferroelectric pellets.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제55권6호
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• pp.323-327
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• 2006

In this paper a new wire-wire discharge system with a slit dielectric harrier has been proposed, and, its corona discharge and ozone generation characteristics have been investigated experimentally. When the slit mica barrier is installed between corona wires, instead of the grounded plate electrode, a significant increase in the generation of ozone, about 2.2 times higher than that of the conventional ones without the slit harrier, could be obtained. Photographs show that this type of discharge system with a slit barrier was found to produce a corona discharge twice, once from the upper and bottom corona wires, and. again from both sides of surfaces and slits of the slit barrier. As a result, the proposed discharge system has the potential to increase significantly ozone production and it may be useful as an effective means for removing pollutant gases.