• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.134-139
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• 2008

This research investigated variations of the engine performance and the exhaust emission characteristic of a direct injection diesel engine by fueling a commercial diesel fuel, which was blended with the di-ether group (butyl-ether: BE). The smoke emission reduced to 26% from the diesel engine with the blending fuel (diesel fuel 80 vol-% + BE 20 vol-%)at the full engine load of 2500 rpm compared to it with the diesel fuel only. The power, torque and brake specific energy consumption of the diesel engine showed very slight differences. The NOx emission from the diesel engine, however, with the blended fuel was higher than with the commercial diesel fuel only. By applying EGR method, as a counter plan of the NOx reduction, this research obtained reductions of the smoke and NOx emission at the same time from the diesel engine with the BE blended diesel fuel.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.3 s.246
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• pp.208-214
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• 2006

Dimethoxy methane$(CH_3-O-CH_2-O-CH_3)$, also known as methylal or DMM, is an oxygenated additive that contains 42.5% oxygen by weight and is soluble in diesel fuel. It is a colorless liquid and a gas-to-liquid chemical 방tat has been evaluated for use as a diesel fuel component. Experiments were conducted by using the five blends with different volumetric percentage of DMM(2.5, 5, 7.5, 10, and 12.5%) in baseline diesel fuel. The test engine was single cylinder, four stroke, DI diesel engine unmodified. Also, data was collected for steady state operation at 24 engine speed-load conditions. The focus of this study was to investigate the effects of the addition of oxygenated fuel to diesel fuel on the engine-out emissions and the performance. Smoke emissions of all DMM blends were reduced substantially in comparison with conventional diesel fuel. These results indicate that DMM may be an effective blendstock for diesel fuel as an environment-friendly alternative fuel. Besides, this study showed that simultaneous reduction of smoke and NOx emissions could be achieved by oxygenated fuel and EGR method that was applied to decrease NOx emissions increasing with smoke emissions reduction.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.15-16
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• 2005

In this study, the characteristics of NOx reduction by using charge air moisturizer system were evaluated by engine performance simulation in medium speed diesel engines. The results of performance simulation were verified by experimental results of single cylinder medium speed diesel engine equipped with charge air moisturizer system. Performance simulation was carried out to evaluate charge air moisturizer system of turbocharged diesel engine, HYUNDAI HiMSEN 9H25/33 engine. Those results show 50% NOx reduction at dew point $80^{\circ}C$ and charge air pressure 4bar.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.6
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• pp.47-56
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• 2001

Nitrogen oxides(NOx) and smoke emissions of diesel engine are regarded as a source of air pollution, and there is a global trend to enforce more stringent regulations on these exhaust gas emissions. However, the trade-off relation of NOx and smoke is a main obstacle to reduce both of them simultaneously. In this paper, experiments were conducted with an oxygenated fuel(diethyl ether) as an effective way to improve the trade-off relation of NOx and smoke. Exhaust emissions of diesel fuels with DEE were influenced by the additive content of DEE and the injection timing. Especially, DEE effected more at the high engine speed and load than at the low engine speed and load. Diesel fuel blended with DEE 10% was a desirable blend for the simultaneous reduction of NOx and smoke.

• 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 Power System Engineering
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• v.6 no.1
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• pp.27-35
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• 2002

In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated for direct injection diesel engine. It is tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenate blended fuel which has four kinds of mixed ratio. And, the effects of exhaust gas recirculation(EGR) on the characteristics of NOx emission and brake specific fuel consumption rate have been investigated. Dimethyl carbonate(DMC) contains oxygen component 53.3% in itself, and it is a kind of effective oxygenated fuel of carbonate group that the smoke emission of DMC is reduced remarkably in comparison 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 and EGR method.

• 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 ILASS-Korea
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• v.5 no.2
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• pp.28-34
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• 2000

To reduce the soot and NOx simultaneously, a new system of stratified injection is developed. This system discharges stratified diesel-methanol in a D. I. Diesel Engine. Nozzle and delivery valve of conventional injection system were remodeled to inject diesel and methanol from one injector sequently. The quantity of diesel and methanol was controled precisely by micrometers mounted on the injection control lack. The real injection ratio of dual fuel was measured by volumetric ratio. We could confirm the capabilities that soot and NOx simultaneously were reduced by diesel-methanol stratified injection from the results of in-cylinder pressure data obtained from combustion experiment by stratified injection, heat release rate and mass fraction bumed.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.6
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• pp.755-760
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• 1999

To remove nitrogen oxides(NOx) in exhaust gas of diesel engine three-way catalytic process with plasma discharger has great possibilities. Characteristics of NOx removal depends on NO conver-sion to $NO_2$ and /or $HNO_3$ due to high activation energies for NO oxidation and reduction, NOx removal efficiency by using three-way catalytic with plasma discharger indicated about 50% at 40watt power consumption condition.

• Journal of Advanced Marine Engineering and Technology
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• v.23 no.1
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• pp.19-24
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• 1999

In this paper the emission characteristic of the ship's diesel engine with CPP(Controllable Pitch Propeller) were investigated under the passage test on the sea. As the results it is confirmed that the NOx.$CO_x$ concentrations increase as the engine speed increases and the torque decreases. but the amount of NOx, COx emissions(g./k Wh) decrease as the torque increase regardless of the engine speed. Also it is compared with the NOx concentra-tions measured by the two method-ECC(Electrochemical Cell)and CLD(Chemiluminescence Detector)for the correct measurement and the ECC indicated higher value than the CLD.