• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.2
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• pp.215-222
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• 1986

This paper presents the results of investigation, the aim of which was to predict theoretically the processes of thermodynamic cycle of M-combustion chamber type diesel engine. The combustion characteristics in cylinder are evaluated from the energy equation for an thermodynamic system in engine cylinder. In order to predict the combustion pressure in cylinder, the engine is divided in various control volumes. The simulation results of combustion characteristics show that the comparison of computed and measured values brings about the good coincidence.

• Transactions of the Korean Society of Automotive Engineers
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• v.19 no.4
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• pp.16-23
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• 2011

Low temperature combustion is one of the advanced combustion technology in an internal combustion engine to reduce soot and nitrogen oxides simultaneously. In present experiment three kinds of injector were used to investigate the influence of injection angle and number of nozzle holes on the low temperature combustion in a heavy duty diesel engine. Low temperature diesel combustion is realized from the exhaust gas recirculation rate of 60%. Indicated mean effective pressure of low temperature combustion corresponds to the 70% level of conventional diesel engine combustion. Reduction of hydrocarbon and carbon monoxide, which are produced in low temperature combustion because of the low combustion temperature and a deficit of oxygen, was achieved by using various injector configuration. The result of experiment with $100^{\circ}$ injection angle and 8 holes showed that reductions in hydrocarbon and carbon monoxide could be achieved 58% and 27% respectively maintaining the 7% increased indicated mean effective pressure in low temperature diesel combustion compared with conventional injector.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.2
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• pp.64-71
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• 2000

In order to clarify the characteristics of soot formation and oxidation in-cylinder of a diesel engine, it is necessary to diagnose accurately for combustion of in-cylinder. The past techniques for soot measurement have limitations in providing the characteristics of soot in a diesel engine, whereas, laser-based 2D imaging diagnostics have the potential to provide better temporally and spatially resolved measurements of the soot distribution. We rebuilt an optically accessible diesel engine which is similar to the conditions of a conventional engine and tried to measure soot distribution in a cylinder of the diesel engine using laser induced scattering(LIS) and laser induced incandescence(LII). Some results were acquired in this study. LIS and LII signal that show soot distribution of a in-cylinder were taken by ICCD properly. The signal of LIS was intenser than that of LII. Although they have some differences of signal intensity in early combusion period, both of signals show that they are generally similar in late combustion period, after ATDC 50 degree.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.6
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• pp.102-109
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• 1994

As a fundamental study to apply high pressure injection system to direct injection diesel engine, fuel injection system and constant volume combustion chamber were made and the behaviors of evaporating spray with the variation of injection pressure and the ambient gas temperature were observed by using high speed camera, and the combusion characteristics with the variation of injection pressure and A/F ratio were analyzed. As injection pressure increases, spray tip penetration and spray angle increase and, as a results spray volume increases. This helps an uniform mixing of fuel and air. Spray liquid core length decreases as ambient gas temperature increases, while it decreases as injection pressure increases but the effect of ambient gas temperature is dorminant. As injection pressure increases, ignition delay is shortened and combustion rate being raised, maximum heat release rate increases. It become clear that High injection pressure has high level of potential to improve the performance of DI-diesel engine.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.8
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• pp.749-756
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• 2004

While designing shafting in reciprocating machines with internal combustion engines which derive generators, pumps, and vehicles, it is very important to calculate the additional stress of shafting by torsional vibration. In this paper, the transfer stiffness coefficient method which is based on the successive transfer of stiffness coefficient was applied to the calculation of the additional stress of shafting in reciprocating machine by torsional vibration. In order to confirm the effectiveness of the present method, a propulsion shafting with a diesel engine in a vessel was considered as the computational example of shafting in reciprocating machine. The results calculated by the present method were compared with those of the modal analysis method, the mechanical impedance method, and free vibration analysis.