• Journal of Advanced Marine Engineering and Technology
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• v.26 no.4
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• pp.457-463
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• 2002

The closed cycle diesel engine is used in a closed circuit system which has no air breathing. The working fluid as intake mixture are consisted of oxygen, argon and recirculated exhaust gas in order to obtain underwater or underground power sources. In the present study, the high pressure diesel engine which can be operated by the closed cycle system with high intake pressure for increasing the net power rate is designed. It has been carried out to investigate the combustion characteristics of high pressure diesel engine according to the power rate. The maximum cylinder pressure and heat release rate were investigated. Also, major experimental data such as specific fuel consumption rate, oxygen concentrations, fuel conversion efficiency, polytropic exponent, and IMEP were compared with low pressure diesel engine experimental data.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.3
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• pp.98-103
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• 2004

Diesel engine offers superior fuel consumption than gasoline engine of equivalent capacity. For this reason, diesel engines are widely used in heavy duty transport applications. Specially, it has been many years that exhaust gases from gasoline automobile rather than from diesel is the major object concerned by Korea and other countries, and it is strongly required on the reduction techniques on harmful NOx, Soot, CO, He. Thus, this paper focused on the emission reduction and target for this paper is heavy-duty diesel engine equipped with power filter such as wet type air cleaner. In this paper, the performance, exhaust emissions(CO, THC, NOx, Soot) and noise of heavy-duty diesel engine were measured at maximum load condition and the range of 1,000∼2,200rpm. The smoke was measured at FAS(Free Accel Smoke) test mode.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.64-71
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• 2011

Homogeneous charge compression ignition (HCCI) was the best concept able to provide low NOx and PM in diesel engine emissions. This new alternative combustion process was mainly controlled by chemical kinetics in comparison with the conventional combustion in internal combustion engine. In this paper, detailed kinetic reaction mechanisms of diesel surrogate was investigated to understand the diesel HCCI engine combustion. It was tested two existing mechanisms and two new mechanisms for the comparison of experimental result. The best mechanism for diesel surrogate was suggested through this comparison.

• International Journal of Automotive Technology
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• v.6 no.3
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• pp.197-203
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• 2005

This paper investigates the effect of oxygen composition in mixed fuel on the exhaust emissions for the direct injection diesel engine. These effects were tested to estimate the change in engine performance and exhaust emission characteristics when commercial diesel fuel and oxygenates blended fuels at a certain fuel and mixed ratio are used. Individual hydrocarbons $(C_1-C_6)$ in exhaust gases, as well as the total amount of hydrocarbons, were analyzed by using gas chromatography to find the mechanism by which smoke emission was remarkably reduced for various oxygenated fuels. The chromatograms between a diesel fuel and a diesel fuel blended DGM (diethylene glycol dimethyl ether), MTBE (methyl tert-butyl ether) and EGBE (ethylene glycol mono-n-butyl ether) were compared. The results showed that the number of individual hydrocarbons as well as the total number of hydrocarbons of oxygenated fuel reduced more remarkably than those of diesel fuel.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.101-110
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• 2002

In this paper, the effects of oxygen component in blended fuel on the exhaust emissions have been investigated far direct injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for th? commercial diesel fuel and oxygenated blended fuels which have three kinds of fuels and various mixed rates. And, it was tried to analyze not only total hydrocarbon but individual hydrocarbons(C$_1$∼ C$\_$6/) in exhaust gases using gas chromatography to seek the reason far remarkable reduction of smoke emission on various oxygenated fuels. This study carried out by comparing the chromatogram with diesel fuel and diesel fuel blended DGM(diethylene glycol dimethyl ether), MTBE(methyl tart-butyl ether) and EGBE(ethylene glycol mono-n-butyl ether). The results of this study show that individual hydrocarbons as well as total hydrocarbon of oxygenated fuel are reduced remarkably compared with commercial diesel fuel.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2004.11a
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• pp.233-236
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• 2004

An experimental study was conducted to evaluate characteristic variation of diluted engine oil by diesel fuel and its effects on engine components. Especially, engine oil was made to have $15\%$ fuel content. To predict existing diesel fuel content in engine oil after test was used the viscosity calibration curve. About $54\%$ percent of diesel fuel in diluted engine oil was distillated by various paths related to reciprocating motion of piston and the rest diesel fuel plays an important role for decreasing engine oil viscosity. Test results show that lowered engine ell viscosity by diesel fuel dilution become a reason of increasing engine elements wear, Therefore, this caused the quantity of blow-by gas to increase and main gallery pressure to decrease.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.65-72
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• 2002

The closed cycle diesel system is operated in closed circuit system where there is non air breathing with working fluid consists of combination of oxygen, argon and recycled exhaust gas far obtaining underwater or underground power sources. Experimental apparatus using the MTU8V183SE92 high pressurized engine adapted for closed cycle running, capable of operating at the system pressure of maximum 5 bar is constructed with ACAP as data acquisition system in order to operate equally in the open cycle in surface or the closed cycle in submerged conditions. The general features and the characteristics of combustion of HP(high pressure) diesel engine, specially designed and manufactured only for CCDE, are investigated. The test results of performance of HP diesel engine in closed cycle system are presented with respect to power and boost pressure and compared with those of low pressure diesel engine. The oxygen concentration and specific heat ratio are investigated with its deviation

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.3
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• pp.88-94
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• 2010

In this paper, the effect of the ultrasonic energy on the diesel engine's smoke reduction has been investigated for indirect injection diesel engine. The smoke concentration of the ultrasonically reformed diesel fuel was reduced remarkably in comparison with conventional diesel fuel. And in-cylinder pressure, heat release rate and mass fraction burned was improved but combustion duration was decreased. However, The combustion durations and the smoke concentrations of both diesel fuels were proportional to the increases of engine loads. Also, When the combustion duration has been increasing, the smoke emission has been augmenting in the shape of the exponential functions.

• Journal of Biosystems Engineering
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• v.32 no.5
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• pp.279-283
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• 2007

In this study, the potential possibility of oxygenates on di-ether group (DBE, dibutyl ether) was investigated as an additives for an agricultural direct injection diesel engine. It tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenates additives blending fuel which has four kinds of mixed ratio. The smoke emission of blending fuel (diesel fuel 80 vol-% + DBE 20 vol-%) was reduced in comparison with diesel fuel, that is, it was reduced approximately 26% at 2500 rpm, full load. And, power, torque and brake specific energy consumption didn't have large differences. But, NOx emission of blended fuel was increased compared with commercial diesel fuel.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.2
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• pp.175-182
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• 1999

Scanning electron microscopy (SEM) has played an important role in receptor modeling area because it is a powerful tool for characterizing individual particles. The purpose of the study was to classify individual diesel particles base on statistical analysis and image analysis by SEM/EDX (energy dispersive x-ray analyser). The diesel particles were sampled by both a modified CVS 75 mode and a high speed mode with a chassis dynamometer. The SEM/EDX system provides various physical parameters including particle's particle diameter and chemical information. Thus density and mass of the diesel particle were estimated cased on its chemical composition and further fractal dimensions of the diesel particle were obtained by the Hurst exponent method. The fractal dimension in the sample of modified CVS 75 mode was higher than the high speed mode. Finally, mass fractions for a diesel vehicle as a source profile were estimated cased on a particle class concept.