• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2004.05a
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• pp.475-478
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• 2004

we studied the effect of the type of non-thermal plasma on the decomposition of $CF_4$. 3 types of reactors were manufactured to generate different types of plasma respectively, and went into the experiments. As the results, we found that high density of the energy of non-thermal plasma and the minimization of non-discharged area should be met in order to elevate decomposition rate of $CF_4$. Among the reactors used in the study, the hole-type reactor was such one that satisfying that requirement. Using the hole-type reactor, treatment efficiency for high concentration of $CF_4$ was excellent. We got decomposition rate of more than 95[%] between 500[ppm] around and less than 400[ppm], and up to 85[%] at 900[ppm].

• Proceedings of the Safety Management and Science Conference
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• 2013.04a
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• pp.655-668
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• 2013

In this study, a combination of the plasma discharge in the reactor by the reaction surface discharge reactor complex catalytic reactor and air pollutants, hazardous gas SOx, change in frequency, residence time, and the thickness of the electrode, the addition of simulated composite catalyst composed of a variety of gases, including decomposition experiments were performed by varying the process parameters. 20W power consumption 10kHz frequency decomposition removal rate of 99% in the decomposition of sulfur oxides removal experiment that is attached to the titanium dioxide catalyst reactor experimental results than if you had more than 5% increase. If added to methane gas was added, the removal efficiency increased decomposition, the oxygen concentration increased with increasing degradation rate in the case of adding carbon dioxide decreased.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1475-1480
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• 2004

Plasma Enhanced Chemical Vapor Deposition (PECVD) process uses unique property of plasma to modify surfaces and to achieve the high deposition rates. In this study, a vertical thermal RF-PECVD (Radio Frequency-PECVD) reactor is modeled to investigate thermal flow and the deposition rates with various shapes of the showerhead. The showerhead in the CVD reactor has the shape of a ring and gases are injected in parallel with the susceptor, which is a rotating disk. In order to achieve the high deposition rates, we have simulated the thermal flow fields in the reactor with several showerhead models. Especially the effects of the number of injection holes and the rotating speed of the susceptor are studied. Using a commercial code, CFDACE, which uses FVM (Finite Volume Method) and SIMPLE algorithm, governing equations have been solved for the pressure, mass-flow rates and temperature distributions in the CVD reactor. With the help of the Nusselt number and Sherwood number, the heat and mass transfers on the susceptor are investigated. In order to characteristics of measure the flatness of the layer, furthermore, the relative growth rate (RGR) is considered.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.3
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• pp.303-312
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• 2009

In this study, a waveguide system for focusing the electric field is presented to emit the microwave-driven plasma visible light. This system consists of a magnetron for the microwave power supply, the waveguide section for power propagation, and the mesh-type cavity reactor. The quartz bulb containing a dose of sulfur powder and buffer gas Ar is located in the reactor, and forced by the strongly concentrated electric field for generating and exciting the sulfur plasma. That is, the conductor tips are loaded on each inner wall of the waveguide and the reactor, and then the plasma bulb is positioned between the tips, hence focusing the strong electric field on the bulb. Furthermore the waveguide section is designed for minimizing the degradations of matching characteristics according to the variations of the electrical conductivities of plasma at the transitory phase for plasma generation, hence providing the stable operation. Finally, the 2.45 GHz aluminum waveguide system is constructed, and then experiments for emitting the visible light are performed by using 400 W-class magnetron, showing the validity of designed system.

• Resources Recycling
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• v.13 no.1
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• pp.59-67
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• 2004

A universal plasma-chemical module (PChM) for the industrial processing of different hydrocarbon raw material pyrolysis was designed and tested. Laboratory investigations for the plasma-chemical method of acetylene production from natural gas and different coals were made. Similar laboratory tests on the industrial production of acetylene as a raw material for organic syn-thesis were developed using the PChM. A comparison of the suggested plasma-chemical method with the traditional process of acetylene production were carried out. The outlook of the plasma-chemical method was shown.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.414.2-414.2
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• 2016

The optimal configuration of a transmutation reactor based on a low aspect ratio tokamak is determined using coupled analysis of tokamak systems and neutron transport. The inboard radial build of the reactor components is obtained from plasma physics and engineering constraints, while outboard radial builds are mainly determined by constraints on a neutron multiplication, a tritium-breeding ratio, and a power density. It is shown that a breeding blanket model has an impact on the radial build of a transmutation blanket. A burn cycle has to be determined to limit a fast neutron fluence of a plasma facing material below a radiation damage limit.

• Journal of Industrial Technology
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• v.15
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• pp.15-22
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• 1995

We have studied the generation and behavior of negative ions in silane plasmas. The negative ions were formed by homogeneous reaction in silane plasma and the behavior of negative ions were predicted by solving the model equations. The concentration profiles of negative ions were shown as a function of reactor length and time. The effects of process variables such as reactor pressure, flow rate and electrical field strengths on the behavior of negative ions were analyzed.

• Nuclear Engineering and Technology
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• v.52 no.11
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• pp.2460-2470
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• 2020

To study the thermophysical and neutronic properties of thorium-plutonium fuel, a conceptual design of a hybrid facility consisting of a subcritical Th-Pu reactor core and a source of additional D-D neutrons that places on the axis of the core is proposed. The source of such neutrons is a column of high-temperature plasma held in a long magnetic trap for D-D fusionreactions. This article presents computer simulation results of generation of thermonuclear neutrons in the plasma, facility neutronic properties and the evolution of a fuel nuclide composition in the reactor core. Simulations were performed for an axis-symmetric radially profiled reactor core consisting of zones with various nuclear fuel composition. Such reactor core containing a continuously operating stationary D-D neutron source with a yield intensity of Y = 2 × 10¹⁶ neutrons per second can operate as a nuclear hybrid system at its effective coefficient of neutron multiplication 0.95-0.99. Options are proposed for optimizing plasma parameters to increase the neutron yield in order to compensate the effective multiplication factor decreasing and plant power in a long operating cycle (3000-day duration). The obtained simulation results demonstrate the possibility of organizing the stable operation of the proposed hybrid 'fusion-fission' facility.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.247-256
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• 2000

Basic characteristics of non-thermal plasma process to remove C2H4 and NO have been experimentally investigated with a packed-bed type reactor and an ac power supply. The performance of the non-thermal plasma generated by ac power supply was compared with that of a wire-plate type reactor equipped with a pulsed power supply. The result shows that the non-thermal plasma can be effectively generated with an AC power supply that can be easily fabricated with conventional techniques. In order to understand the basic reaction mechanisms of the non-thermal plasma process, parametric tests for different carrier gases(air and nitrogen) and for different reaction pathways have been performed. The test results show that O3 generated by non-thermal plasma plays an dominant role to oxidize C2H4 and NO over N and O radicals when these pollutant gases are carried by dry air under room temperature condition. Experimental observations, however, indicate that N and O radicals can significantly affect on the removal process of the pollutant gases under certain conditions.

• The Korean Journal of Ceramics
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• v.5 no.3
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• pp.245-249
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• 1999

A new type of nonthermal plasma reactor utilizing ferroelectric pellets is proposed to generate nonthermal plasma efficiently, which is used for simultaneous control of various pollutant gases. Electric charges stored on ferroelctric pellets by corona discharge between a corona tip and a mesh electrode provide partial electrical discharges among ferroelectric pellets. These partial electrical discharges can enhance partial discharges around the surface of ferroelectric pellets. This method utilizes wide reacting area of ferroelectric pellets and partial discharge. Positive and negative dc voltage are applied to the corona tip to generate partial discharges, and corona currents are estimated to investigate charge storage on ferroelectric pellets as function of time and charge relaxation time constants of ferroelectric pellects. As a result, charge relaxationtime, dielectric constants of ferroelectric pellets, polarity of applied voltage and applied time influence partial discharges among ferroelectric pellect.