• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2082-2087
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• 2004

In this study, the variation of spark plug location in the combustion chamber was investigated for the sake of emission characteristics from SI engine by using PDA valve. The swirl is ong of the important parameters that effects emission characteristics. PDA valve has been used to satisfy the requirements of sufficient swirl generation to improve combustion and emission reduction to effect on flow profile on a combustion chamber. Especially, the variation of spark plug location have an important effect to analyze exhaust gas and the early flame propagative process. Therefore, this test is forced that injection timing, spark timing and intake air motion govern the stable combustion. From the results, it showed that the variable spark plug location and PDA valve can be reduced exhaust gas.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.10
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• pp.1163-1171
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• 2004

The variation of spark plug location have one of the effects on combustion characteristics. Several parameters of the effect on combustion characteristics are shape of combustion chamber, the spark plug position, turbulence flow and so on. This paper presents an experimental study according to variation of spark plug protrusion and PDA valve which have effects on characteristics of combustion and emission in single cylinder gasoline engine. Also, this paper emphasized that combustion stabilization was making by way of the reinforcement of the turbulent flow with the PDA valve. A feasibility and necessity of combustion pressure based cylinder spark timing control according to spark plug protrusion has been examined. So, this was obtained COV$\_$imep/ and the mass fraction burned(MFB) and the specific fuel consumption(sfc). Using the results of the test, the effects of the variable spark plug location and PDA valve can be improved fuel consumption and be available for the combustion stability.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.32-40
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• 2005

The purpose of this study is to investigate variation of spark plug protrusion and PDA valve on the exhaust emission in a gasoline engine. Swirl is one of the important parameters that affects the characteristics of combustion. PDA valve has been developed to satisfy requirements of sufficient swirl generation for improving the combustion and reducing of emission level. Also, especially, the variation of spark plug protrusion have an important effect to the early flame propagative process. This is largely due to the high flame speed by short of flame propagation distance. So, this is forced that injection timing, spark timing and intake air motion govern the stable combustion. As a result, using two combustion chamber, without charge of engine specification and the variable spark plug location and PDA valve could be reduced exhaust gas at a part load engine conditions(1500rpm imep 3.9bar, 2000rpm imep 3.2bar, 2400rpm imep 3.9bar).

• Journal of Mechanical Science and Technology
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• v.14 no.8
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• pp.891-899
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• 2000

The flame speed may be decomposed into the burning speed and the flame transport speed. The flame transport speed is affected considerably by the flow direction, variation rate of flow direction, and flow speed in the combustion chamber. Especially, the flow direction and the variation rate of flow direction at the spark plug location during the ignition period have an important effect on the ignition process and the early flame propagation process. We measured the flow direction component and the variation rate of flow direction with a hot wire probe at the spark plug location. It was shown that the representative flow direction of ignition period is the right-vertical direction of crank shaft and it was used to investigate the variation rate of flow direction.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2423-2430
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• 1994

Several factors of the efficient combustion process are shape of combustion chamber, position of spark plug, turbulence flow and so on. the shape of combustion chamber and position of spark plug are constrained to geometrically, and then it could not make a change the shape easily. But the turlence flow in combustion chamber have a great influence on combustion phenomena, and which is much easier to control relatively. And since characteristics of turbulence flow would be very important to the stability of combustion and performances, This study is also essential to future engine-low emission and lean burn engine. This paper shows that the visualization of the turbulence flow of single cylinder engine by using 2way, $45^{\circ}$ inclined and 2 channel hot wire probe through the park plug hole. We also study the characteristics of turbulence flow by means of ensemble averaged mean velocity, turvulence intensity and integral length scale.

• Journal of ILASS-Korea
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• v.28 no.4
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• pp.198-206
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• 2023

In this study, visualization of in-cylinder spray behavior and spark channel stretching by air flow characteristics depending on engine operating conditions were investigated. For in-cylinder spray behavior, increase in engine rpm did not alter the counter-clockwise air flow direction and location of in-cylinder dominant air flow but increased average air flow velocity, which hindered spray propagation parallel to the piston surface. When injection timing was retarded, direction of in-cylinder dominant air flow was changed, and average air flow velocity was reduced resulting in an increase in spray penetration length and change in direction. For spark channel stretching, increase in air flow speed did not affect spark channel stretch direction but affected length due to increase in spark channel resistance and limitation of energy ignition coil can handle. Change in air flow direction affected spark channel stretch direction where the air flow was obstructed by ground electrode which caused spark channel direction to occur in the opposing direction of air flow. It also affected spark channel stretch length due to change in air flow speed around the spark plug electrode from the interaction between the air flow and ground electrode.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.7
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• pp.1398-1407
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• 1992

The prediction of heat loss during laminar flame propagation was carried out by measurement of gas pressure and visualization of flame propagation in the constant volume combustion chamber. And to validate the prediction, the instantaneous temperature at wall of combustion chamber was also measured. Consequently, it was found that heat loss was increased according to increasing of maximum flame travel distance, but rate of heat loss for heat release during laminar flame propagation was nearly constant. And heat loss depends on heat transfer area which was contacted the wall by burned gas regardless to spark plug location.