• Journal of the Korean Institute of Gas
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• v.4 no.2 s.10
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• pp.1-6
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• 2000

In this experiment, we made the plasma reactor which adhere needle electrode in order to treat safely an NOx which was included in the gas. Also we experimently investigated characteristics of equipment and inspected efficiency. As a reaction gas, by using mixture gas of $NO/N_2$ and $N_2/O_2$, we setted up initial NO concentration and gas flow rate was set at 2 ${\iota}$/min. As a reaction characteristics of NOx, when discharge input power was high, NO concentration decreased and when the oxygen concentration increased, the NO decomposition was easy and decomposition energy efficiency was high. Also in case that NO concentration increased, NO decomposition energy efficiency was high but decomposition rate was low. The characteristics of ozone, when discharge input power was high, ozone increased and when $NO/N_2$ concentration increased, the ozone decreased.

• 한국연소학회:학술대회논문집
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• 2006.10a
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• pp.104-109
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• 2006

Improvements in internal combustion engine and aftertreatment technologies are needed to meet future environmental quality goals. Plasmatron fuel converters provide a rapid response, compact means to transform a wide range of hydrocarbon fuels (including gasoline, natural gas and diesel fuel) into hydrogen-rich gas. Hydrogen-rich gas can be used as an additive to provide NOx reductions of more than 80% in diesel engine vehicles by enabling very lean operation or heavy exhaust engine recirculation. For diesel engines, use of compact plasmatron reformers to produce hydrogen-rich gas for the regeneration of NOx absorber/absorbers and particulate traps for diesel engine exhaust after-treatment could provide significant advantages. Recent tests of conversion of diesel fuel to hydrogen-rich gas using a low current plasmatron fuel converter with non-equilibrium plasma features are described.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.365-365
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• 2008

In this work, Ga-doped ZnO (GZO) thin films for NOx gas sensor application were deposited on low temperature co-fired ceramics (LTCC) substrates, by RF magnetron sputtering method. The LTCC substrate is one of promising materials for this application since it has many advantages (e.g., low cost production, high manufacturing yields and easy realizing 3D structure etc.). The LTCC substrates with thickness of 400 pm were fabricated by laminating 12 green tapes which consist of alumina and glass particle in an organic binder. The structural properties of the fabricated GZO thin films with different thickness are analyzed by X-ray diffraction method (XRD) and field emission scanning electron microscope (FESEM). The GZO gas sensors are tested by gas measurement system under varing operation temperature and show good performance to the NOx gas in sensitivity and response time.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.3
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• pp.85-91
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• 2003

In this study, the potential possibility of oxygenated fuel such as Methyl tertiary butyl ether (MTBE) was investigated for the sake of exhausted smoke reduction from diesel engine. MTBE has been used as a fuel additive blended into unleaded gasoline to improve octane number, but the study of application for diesel engine was incomplete. Because MTBE includes oxygen content approximately 18%, it is a kind of oxygenated fuel that the smoke emission of MTBE is reduced remarkably compared with commercial diesel fuel. But, the NOx emission of MTBE blended fuel is increased compared with commercial diesel fuel. And, it was tried to analyze not only total hydrocarbon but individual hydrocarbon components from $C_1$ to $C_6$ in exhaust gas using gas chromatography to seek the reason for remarkable reduction of smoke emission. Individual hydrocarbons($C_1$~$C_6$) as well as total hydrocarbon of oxygenated fuel are reduced remarkably compared with diesel fuel. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission has been investigated, too. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel and cooled EGR method.

• Journal of Mechanical Science and Technology
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• v.15 no.11
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• pp.1588-1598
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• 2001

The effects of recirculated exhaust gas on the characteristics of NOx and soot emissions under a wide range of engine loads were experimentally investigated by using a four-cycle, four-cylinder, sw irl chamber type, water-cooled diesel engine operating at three engine speeds. The purpose of this study was to develop the EGR-control system for reducing NOx and soot emissions simultaneously in diesel engines. The EGR system is used to reduce NOx emissions, and a novel diesel soot removal device with a cylinder-type scrubber for the experiment system was specially designed and manufactured to reduce soot contents in the recirculated exhaust gas to the intake system of the engine. The experiments were performed at the fixed fuel injection timing of 4$^{\circ}$ ATDC regardless of experimental conditions. It was found that soot emissions in exhaust gases were reduced by 20 to 70% when the scrubber was applied in the range of the experimental conditions, and that NOx emissions decreased markedly, especially at higher loads, while soot emissions increased owing to the decrease in intake and exhaust oxygen concentrations, and the increase in equivalence ratio as the EGR rate is elevated.

• 한국연소학회:학술대회논문집
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• 2003.05a
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• pp.301-310
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• 2003

Eco-Machinery engineering technologies in KIMM for reducing NOx emission were introduced. Combustion technologies such as reburning and fuel staged or air staged combustion have been applied to reduce NOx emission in the field of boiler furnaces. Lean premixed combustion method have been studied in gas turbine combustor. Hybrid system with plasma and SCR being considered as prospective method of De-NOx has been developed. Also, low NOx technologies including common rail system, EGR and DPF in diesel engine have been investigated.

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.1
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• pp.76-88
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• 1995

The effects of exhaust gas recirculation(EGR) on the characteristics of NOx emissions and specific fuel consumption rate have been investigated using an eight-cylinder. four cycle. direct injection diesel engine operating at several loads and speeds. The theoretical NO formation concentration is calculated with the equivalence ratio as a parameter of flame temperature to study the effect of EGR on NOx emissions in the diesel combustion. The experiments in this study are conducted on the fixed fuel injection timing of $38^{\circ}$ BTDC regardless of experimental conditions. It is found that the specific fuel consumption rate is slightly increased with EGR rate. and NOx emissions are markedly reduced owing to the drop of the incoming oxygen concentratio and the increase of equivalence ratio as the EGR rate increases.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.5
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• pp.79-84
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• 2011

Air pollutants from a small marine diesel engine are increasing and the IMO(International Marine Organization) regulation asked for its reduction. In this study, NOx reduction technologies such as improvement of various cooling systems are applied to the small marine diesel engine. The various cooling systems are a intercooler, a heat exchanger for engine coolant, and an exhaust manifold by water cooling. These systems are tested on an engine dynamometer and a exhaust gas analyzer by a marine diesel engine test regulation. Test results are shows that the small marine engine are satisfied the IMO NOx regulations; Tire II.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.66-72
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• 2004

In this study, the effects of oxygen component in fuel and exhaust gas recirculation(EGR) method on the exhaust emissions has been investigated for a D.I. diesel engine. It was tested to estimate change of exhaust emission characteristics for the commercial diesel fuel and oxygenate blended fuel which has five kinds of blending ratio. Dimethoxy methane(DMM) contains oxygen component 42.5% in itself, and it is a kind of effective oxygenated fuel for reduction of smoke emission. It was affirmed that smoke emission was decreased with increasing of DMM blending ratio. But, NOx emission was increased compared with commercial diesel fuel. It was needed a NOx reduction counterplan that EGR method was used as a countermeasure for NOx reduction. It was found that simultaneous reduction of smoke and NOx emission was achieved with DMM blended fuel and cooled EGR method(1015%).

• Electrical & Electronic Materials
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• v.10 no.8
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• pp.807-811
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• 1997

In this paper we have investigated the removal characteristics of NOx by pulsed corona discharge with a multi-pointplane electrode where a magnetic field is applied in the discharge region. The efficiency of NOx removal was measured and analyzed as a function of pulse frequency gas flow rate NOx initial concentration magnetic flux density. In this result the highest removal efficiency of NOx was obtained at the following operating conditions; the frequency =400[Hz] gas flow =1[$\ell$/min] initial concentration= 400[ppm] and magnetic flux density=0.36[T].