• Journal of ILASS-Korea
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• v.6 no.1
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• pp.1-8
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• 2001

Fuel injection system is very important in diesel combustion. Recently electronic control of fuel injection system and common rail systems are introduced to reduce the emission and to increase the energy efficiency from diesel engine by control of the injection timing and duration. In this study, evaluation possibility of the system for electronic control by spool valve, one of the accumulator type injection systems with spool valve using solenoid was composed and the operating characteristics were investigated to evaluate the effects of spring coefficient, initial spring force, solenoid driving time, fuel supply pressure on the injection timing and duration. We could confirm the capability that diesel injection was electronically controlled by spool valve.

• Journal of ILASS-Korea
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• v.3 no.2
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• pp.24-33
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• 1998

The characteristics of liquefied butane spray are expected to be different from conventional diesel fuel spray, because a kind of flash boiling spray is expected when the back pressure is below the saturation vapor pressure of the butane(0.23MPa at $25^{\circ}C$). An accumulator type pintle injector and its fuel delivery system has been simulated in ruder to give injection pressure, needle lift and rate of fuel injected. The governing equation were solved by finite difference metho. The injection duration was controlled by solenoid valve. Spray behaviors such as a transient spray tip penetration, spray angle and SMD were calculated based on the empirical correlations in case that the back pressure is both above the vapor pressure of the butane and below that of butane. When the back preassure is below the vapor pressure of the fuel, conventional correlation is modified to represent the effect of flash boiling.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.8
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• pp.1101-1110
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• 1998

Computational investigation was conducted to examine the performance of a high pressure common-rail fuel injection system which is used to power a passenger car direct injection (Dl) diesel engine. The pipe flows were modeled by one dimensional wave equation and solved by implicit FDM Each volume of injector was considered as chambers with orifice nozzle in connections. These simulation results were compared with the experimental data of Ganser Hydromag. The comparison of needle life and rate of injection between simulation data and experimental data showed quite a good agreement Different shape of injection rate can be made by adjusting the size of inlet orifice and exit orifice in the piston chamber The pilot injection was accomplished by adjusting command signal.