• Journal of Energy Engineering
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• v.15 no.3 s.47
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• pp.139-145
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• 2006

The purpose of this study is to obtain low-emission and high-efficiency in LPG engine with hydrogen enrichment. The objective of this paper is to clarify the effects of hydrogen enrichment in LPG fuelled engine on exhaust emission, thermal efficiency and performance. The compression ratio of 8 was selected to avoid abnormal combustion. To maintain equal heating value of fuel blend, the amount of LPG was decreased as hydrogen was gradually added. The relative air-fuel ratio was increased from 0.8 to 1.3, and the ignition timing was controlled to be at MBT (minimum spark advance for best torque)

• Journal of Mechanical Science and Technology
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• v.17 no.8
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• pp.1196-1202
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• 2003

The concept of hydrogen enriched LPG fuelled engine can be essentially characterized as low emissions and reduction of backfire for hydrogen engine. The purpose of study is obtaining low-emission and high-efficiency in LPG engine with hydrogen enrichment. In order to determine the ideal compression ratio, a variable compression ratio single cylinder engine was developed. The objective of this paper is to clarify the effects of hydrogen enriched LPG fuelled engine on exhaust emission, thermal efficiency and performance. The compression ratio of 8 was selected to minimize abnormal combustion. To maintain equal heating value, the amount of LPG was decreased, and hydrogen was gradually added. In a similar manner, the relative air-fuel ratio was increased from 0.8 to 1.3 in increment of 0.1, and the ignition timing was controlled to be at MBT each case.

• Journal of ILASS-Korea
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• v.14 no.1
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• pp.28-33
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• 2009

This paper presents the performance and emissions characteristics of a small spark-ignited 2-stroke gasoline and LPG engine. The engine used in this paper is a single cylinder, two-stroke, air-cooled SI engine for brush cutter. We measured the rpm, torque, fuel consumption and HC, CO, NOx emissions in associated with the dynamometer load at WOT. The results showed that as engine revolution speed decreased, the excess air ratio of gasoline engine kept going about 0.9 and that of LPG engine increased 0.83 to 1.05. Torque and power of gasoline engine was higher than LPG engine. In exhaust emissions, HC emissions of gasoline engine was lower than LPG engine. In low speed area, CO emissions of LPG engine was lower than gasoline engine. Both gasoline engine and LPG engine emitted little NOx emissions.

• Journal of Korean Society of Disaster and Security
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• v.10 no.2
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• pp.29-34
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• 2017

LPG is a substance that requires a lot of attention because it can cause fatal damage to people and environment when an accident occurs. LPG is frequently accidents in transportation facilities as well as fixed facilities, among which LPG tank lorries are the most frequent accidents. When the LPG tank is evacuated, the LP gas leaks into two phases, leaks mostly to the gas and leaks to some liquid. At this time, the leaked gas will also sink downward because it is heavier than air, and if it continues to leak, it may form an explosion and explode by the ignition source. The purpose of this study is to present the evacuation distance by analyzing the effect distance of the LPG liquefied petroleum gas in the event of explosion. As a result of calculation of the scattering radius of the fragment, the cylinder fragment was scattered up to 561 m. Therefore, it is appropriate to set the distance to be escaped when the LPG tanker leaks to 561m or more.

• Journal of the Korean Institute of Gas
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• v.25 no.2
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• pp.22-27
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• 2021

This paper is a purpose to study the failure examples for LPG vehicle. The first example, the researcher certified the incongruity phenomenon decreased engine power by ignition fire leakage because of spark plug threaded part damage assembling in cylinder head. The second example, the timing mark that accurately adjusting the camshaft and crankshaft position were twisted about 0.5 block each other. Finally, the researcher seeked the disharmony phenomenon as it couldn't set ignition timing. The third example, the researcher knew the failure phenomenon by interrupted the closing period for intake valve moving with air flow in the number 3 port of cylinder head as the foreign substance in cylinder head didn't remove. Therefore, the manager of a car has to thorough going inspect and the manufacture of a car must remove the cause of failure with quality assurance.

• 연구논문집
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• s.33
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• pp.5-16
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• 2003

Fuel distribution, combustion, and flame propagation characteristics of heavy duty engine with the liquid phase LPG injection(LPLI) were studied in a single cylinder engine. Optically accessible single cylinder engine and laser diagnostics system were built for quantifying fuel concentration by acetone PLIF(planar laser induced fluorescence) measurements. In case of Otto cycle engine with large bore size, the engine knock and thermal stress of exhaust manifold are so critical that lean burn operation is needed to reduce the problems. It is generally known that fuel stratification is one of the key technologies to extend the lean misfire limit. The formation of rich mixture in the spark plug vicinity was achieved by open valve injection. With higher swirl strength(Rs=3.4) and open valve injection, the cloud of fuel followed the flow direction and the radial air/fuel mixing was limited by strong swirl flow. It was expected that axial stratification was maintained with open-valve injection if the radial component of the swirling motion was stronger than the axial components. The axial fuel stratification and concentration were sensitive to fuel injection timing in case of Rs=3.4 while those were relatively independent of the injection timing in case of Rs2.3. Thus, strong swirl flow could promote desirable axial fuel stratification and, in result, may make flame propagation stable in the early stage of combustion.

• Journal of the korean Society of Automotive Engineers
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• v.7 no.2
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• pp.64-79
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• 1985

Engine performances and emission characteristics were investigated, using a experimental single cylinder engine with methanol-LPG(butane) fuel blend. The results were compared with the case of neat methanol and gasoline. The blending ratio of methanol to LPG was reasonable at 90 : 10(M90) and in using M90, the engine performances including output, brake specific fuel consumption and brake thermal efficiency, were better than those of neat methanol and gasoline. CO emission of M90 was lower than that of meat methanol by 15% and lower than that of gasoline by 35%. HC emission of M90 was also lower than that of gasoline by 46-85% in the whole range of .phi. The concentration of NOx emission of M90 was lower than that of gasoline and higher than that of neat methanol.

• International Journal of Automotive Technology
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• v.2 no.4
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• pp.147-155
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• 2001

Analysis of the thermodynamic cycle of IC engine from the point of view of economy and emissions was carried out. From this analysis potential capability of engine development was derived. This potential capability is lean-burn engine, fuelled with homogeneous mixture with $\lambda \geq$ 1.4. Several different modes of fuelling were proposed and tested on one-cylinder test engine from the point of view of extending lean operating limit of the engine, emissions and fuel economy. Among them were: fuelling with evaporated preheated gasoline, with gas (LPG evaporated) and with liquid butane. From these modes, fuelling with liquid butane injected to inlet port was selected and finally tested. This novel system of fuelling offered better than standard engine performances and emissions at lean operating limit. These results were validated on full-scale two-cylinder engine.

• Journal of ILASS-Korea
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• v.14 no.3
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• pp.103-108
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• 2009

This research investigated spray characteristics using LPG fuel under compression ignition to contribute to develop a high efficiency LPG fuel is an environmentally-friendly fuel since it emits lower $CO_2$ compare to other conventional fuels. In order to observe spray process, a high speed digital camera and high pressure common-rail injector were applied. Using the spray behaviors of LPG and diesel fuel from the experiment, this research analyzed the mixing process of air-fuel mixture numerically with FLUENT 6.3 when LPG and diesel fuel injected directly into the cylinder while compression stroke occurs. Spray characteristics of LPG fuel was investigated by using numerical method, in which KH-RT model was adapted for phase change. As a result of numerical analysis, this work found out that LPG spray has a wider mixing formation and uniform diffusion of air-fuel mixture compare to diesel.

• Journal of ILASS-Korea
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• v.27 no.2
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• pp.94-100
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• 2022

Even in non-road UTV (Utility Terrain Vehicle), spark ignition engines are often used to reduce emissions. In this study, gasoline and LPG (Liquified Petroleum Gas) fuels were applied to UTV engines, and the exhaust gas and combustion stability were compared through engine tests. A 0.8-liter two-cylinder SI engine was used in the experiment. Experiments were conducted while changing the IVO (Intake Valve Open) and EVC (Exhaust Valve Close) at 1500 rpm 14 N·m, 40 N·m, and 3000 rpm 17 N·m, 44 N·m conditions. As a result of the experiment, when the valve overlap increased according to the change of IVO and EVC, combustion stability decreased and THC emission increased, but NOx decreased. Comparing the LPG engine with the gasoline engine, the amount of CO₂ and PN (Particulate Number) generation decreased in the LPG engine, and the combustion stability was good.