• 동력기계공학회지
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• 제9권3호
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• pp.15-20
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• 2005

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated for an indirect injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenated blended fuel which has four kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission have been investigated. Ethylene glycol mono-n-butyl ether(EGBE) contains oxygen component 27% in itself, and it is a kind of effective oxygenated fuel of mono-ether group that the smoke emission of EGBE is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads and speeds in diesel engine. It was found that simultaneous reduction of smoke and NOx was achieved with oxygenated fuel(10vol-%) and cooled EGR method(10%).

• 한국가스학회지
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• 제22권3호
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• pp.7-12
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• 2018

화석연료를 연소할 때 연소로 내의 고온의 온도 분위기에서 열적 질소산화물이 발생하게 된다. 연소기기에서 질소산화물을 저감하기 위한 여러 가지 방법 중에 배기가스 재순환 방법이 널리 쓰이고 있다. 본 연구에서는 배기가스 재순환 배관에 코안다 노즐을 사용하고 양쪽 출구가 트인 재순환하는 버너에 대하여 냉간 유동 특성을 전산유체해석을 통해 살펴보았다. 재순환 배관이 원통 버너의 접선방향으로 설치되어 있어서 버너 내부에서 선회유동이 형성되어 원통 버너 중심 부분에 역류가 생기는 현상을 관찰하였으며 이는 한쪽이 막힌 재순환 버너와 유사한 경향임을 확인 하였다. 본 연구로부터 양쪽 출구가 트인 재순환 버너에서 재순환 유입량은 한쪽이 막힌 버너보다 약 5% 증가하는 것을 확인하였고 양쪽 트인 버너에서 배기가스 재순환 배관의 유입구 위치의 출구에서는 전체 영역에서 유입 유동이 형성되고 반대편의 출구에서는 총 유량은 배출되지만 원통의 가운데 부분은 역류가 일어나는 것을 확인하였다. 배출되는 출구에서 배출되는 유량은 유입되는 출구에서의 유입량보다 3~5배 유량이 크게 나타났다.

• 동력기계공학회지
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• 제8권1호
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• pp.18-23
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• 2004

The direct injection diesel engine is one of the most efficient thermal engines. For this reason DI diesel engines are widely used for heavy-duty applications. But the world is faced with very serious problems related to the air pollution due to the exhaust emissions of diesel engine. So, that is air pollution related to exhaust gas resulted from explosive combustion should be improved. Exhaust Gas Recirculation(EGR) is a proven method to reduce NOx emissions. In this study, the experiments-were performed at various engine loads while the EGR rates were set from 0% to 20%. The emissions trade-off and combustion of diesel engine are investigated. Hot and cooled EGR are achieved without cooling and with cooling respectively. It was found that the exhaust emissions with the EGR system resulted in a very large reduction in oxides of nitrogen at the expense of higher smoke emissions. Also, the reduction rates of NOx emissions for hot and cooled EGR are similar at load 20%.

• International Journal of Automotive Technology
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• 제2권4호
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• pp.123-133
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• 2001

An important goal in diesel engine research is the development of a means to reduce the emission of oxides of nitrogen ($NO_x$) and soot particulate. A phenomenological model based on the multizone concept is used in the current paper to analyze and compare the effects of exhaust gas recirculation (EGR) and split fuel injection on emission from a compression-ignited, direct-injection engine. The present results show that $NO_x$ can be reduced with a minimum penalty of soot particle emission with cooled EGR. Compared with EGR, split fuel injection has a higher soot penalty at a given level of $NO_x$ reduction.

• 한국자동차공학회논문집
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• 제3권1호
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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.

• 대한조선학회 특별논문집
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• 대한조선학회 2017년도 특별논문집
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• pp.54-58
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• 2017

The vessels which are operated in ECA (Emission Control Area) after $1^{st}$ January 2016 shall be complied with revised NOx emission requirement (Tier III). Effective solutions for NOx emission requirement are SCR (Selective Catalytic Reduction), EGR (Exhaust Gas Recirculation) and Installation of LNG Dual Fuel Engine. This study is considered the design modification as per application of LNG Ready notation. In case of LNG Ready - S notation, the vessel shall be retrofitted the Main engine with Dual fuel engine and LNG Fuel system after delivery. On this paper, the entire process for design modification was explained to meet the requirement for LNG Ready notation.

• 한국자동차공학회논문집
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• 제17권3호
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• pp.62-67
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• 2009

In this study, the potential possibility of biodiesel fuel was investigated as an alternative fuel for a naturally aspirated indirect injection diesel engine. The smoke emission of biodiesel fuel was reduced remarkably in comparison with diesel fuel, that is, it was reduced approximately 36% at 2000rpm, full load condition. And, power, torque and brake specific energy consumption showed no significant differences. However, NOx emission of biodiesel fuel was increased compared with commercial diesel fuel. Also, the effects of exhaust gas recirculation(EGR) to reduce the NOx emission has been investigated. It was found that simultaneous reduction of smoke and NOx was achieved with biodiesel fuel(20vol-%) and cooled EGR method$(10{\sim}15%)$.

• International Journal of Automotive Technology
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• 제7권6호
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• pp.659-666
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• 2006

EGR(Exhaust Gas Recirculation) systems are extensively used to reduce NOx emissions in light duty diesel engine but its application to heavy duty diesel engines is yet to be widely implemented. In this study, the simulation model for a EURO 3 engine was developed using WAVE and then its performance and emission levels were verified with experimental results. The possibility of operating a EURO 3 engine with LPL EGR system to satisfy the EURO 4 regulation was investigated. Each component of the engine was modeled using CATIA and WaveMesher. The engine test mode was ESC 13, and the injection timing and fuel quantity were changed to compensate for the reduction of engine power caused by applying EGR. As a result of the simulation, it was found that EURO 4 NOx regulation could be satisfied by applying an LPL EGR system to the current EURO 3 engine.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2015년도 제51회 KOSCO SYMPOSIUM 초록집
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• pp.41-44
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• 2015

Experimental study was conducted to investigate the effect of ultra-high injection pressure on combustion and emission characteristics in a single-cylinder diesel engine. Electronically controlled ultra-high pressure fuel injection system consistently supplied the fuel of ultra-high pressure up to 250 MPa. Various injection pressures, 40 to 250 MPa, were applied and compared. A injector with eight identical nozzle holes which have diameter of $105{\mu}m$ was used. The results showed high potential to improve the nitrogen oxide (NOx) and particulate matter (PM) trade-off relationship with an ultra-high injection pressure and the exhaust gas recirculation (EGR).

• 오토저널
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• 제8권1호
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• pp.29-39
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• 1986

The purpose of this study is to develop an exhaust gas recirculation valve for reduction of the NOx emission of the gasoline engine. In this study the back pressure modulated(BPM) EGR system was developed and tested for the 1.6$\ell$ gasoline engine. By this system 50% of NOx emission was reduced at 7% EGR rate. Fuel consumption and CO emission were not affected by EGR but HC was increased up to the level of allowable limit. Overall operation was satisfactory. As a result of this study, the technics for developing EGR valve and adjusting the engine for EGR have been established.