• Transactions of the Korean Society of Automotive Engineers
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• v.4 no.4
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• pp.58-71
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• 1996

A model which calculates the hydrocarbon emissions from spark ignition engines is presented The model contains the formation of HC emissions due to both crevices around piston ring top land and oil films on the cylinder wall. The model also considers in-cylinder oxidation and exhaust port oxidation of desorbed HC from crevices and oil films after combustion process. The HC emissions model utilizes the results of SI engine cycle simulation. The model predicts well the trends of HC emissions from the engines when varying engine parameters.

• Journal of Mechanical Science and Technology
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• v.14 no.6
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• pp.699-703
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• 2000

Experiments were carried out to investigate the characteristics of the hydrocarbon (HC) emissions and to reduce cold start hydrocarbons in gasoline engines. An HC adsorber was, used and it coated was by Pd/Rh catalyst with zeolite on a honeycomb monolith. The HCs were efficiently trapped at temperatures below $100^{\circ}C by physical adsorption. After adsorption, they were reduced gradually by the catalytic oxidation of Pd/Rh catalysts as the adsorber temperature increased above $100^{\circ}C. Increasing amounts of methane, ethylene and n-butane were emitted as the fuel-air mixture became richer and the engine speed decreased. As the temperature of adsorber increased, high-number carbons into low-number carbons. Thus, the C4 concentration decreased significantly during the first 30 seconds, and the C2 concentration increased continuously.

• Journal of the korean Society of Automotive Engineers
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• v.3 no.1
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• pp.46-53
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• 1981

This paper describes emission control of hydrocarbon and carbon-monoxide due to oxidizing catalyst. The experiment was performed on a precious metal pelleted catalyst(Pt). The factors of the efficiency for purification due to oxidizing catalyst are space velocity, temperature, composition of exhaust gas and supplementary air. The experiment was carried out to control the factors of efficiency for purification. The results of experimental study show that temperature of catalytic converter, supplementary air and space velocity affected the efficiency for purification of hydrocarbon and carbon monoxide.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.3
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• pp.1-9
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• 2004

During the SI engine starting up, starting conditions directly contribute to the unburned hydrocarbon emissions in spark ignition engines. The effects of catalyst temperatures and fuel injection skip methods on HC emissions were investigated. The test was conducted on a 1.5 L, 4-cylinder, 16 valve, multipoint-port-fuel-injection gasoline engine. To understand the formation of HC emissions, HC concentration was measured in an exhaust port using a Fast Response Flame ionization Detector (FRFID). The result showed that HC emissions, which were emitted at the cold coolant and catalyst temperature, were generated much higher than those of hot coolant and catalyst temperatures. In additions, fuel injection skips reduced highly HC emissions. It is convinced that optimized fuel injection skip method according to coolant and catalyst temperatures could be applied to reduce HC emissions during the SI engine starts.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.2
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• pp.212-219
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• 1998

Unburned hydrocarbon is a key contributor to both the fuel economy and emissions of automotive engine. Cyclic variation of HC emission is of importance, especially during throttle transients. The real time measurement of hydrocarbon is particularly important to obtain a better understanding of the mechanisms for combustion and emissions, especially during cold start and throttle transient condition. This paper reports the cycle resolved measurement technique of unburned hydrocarbons to quantify rapid changes of in-cylinder concentration in the vicinity of spark plug by using the Fast Response Flame Ionization Detector(FRFID). While this instrument actually measures fuel concentration, its results can be indicative of the AFR behaviour. In order to understand the rapid change of hydrocarbons with cylinder pressure, it is necessary to study the response time delay of the system, including the time associated with gas transportation to FID. And signal from FRFID is correlated with cylinder pressure data to relate changes in mixture preparation to the classic analysis, such as indicated mean effective(IMEF) and ignition delay, etc.

• Journal of Hydrogen and New Energy
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• v.26 no.4
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• pp.363-368
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• 2015

Finding an alternative fuel and reducing environmental pollution are the main goals for future internal combustion engines. The purpose of this study is to obtain low-emission and high-efficiency by hydrogen enriched LPG fuel in a LPG engine. An experimental study was carried out to obtain fundamental data for the emit HC emission characteristics at cold start of pre-mixed LPG and hydrogen in a LPG engine with various fractions of hydrogen-LPG blends. To maintain equal volume ratio of fuel blend, the amount of HC was decreased as hydrogen was gradually added. The results showed that as hydrogen increases, in-cylinder pressure increased. Also emission of unburned hydrocarbon (HC) is sharply decreased.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.3 s.258
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• pp.234-241
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• 2007

The regulations for hydrocarbon emission from vehicles have become much more stringent in recent years. These more stringent regulations request vehicle manufacturers to develop the advanced exhaust system for reducing exhaust emissions. The exhaust emissions has many sources in vehicle. In order to investigate the characteristics of hydrocarbon(HC) in the exhaust manifold, concentrations of individual HC species were measured in exhaust process. Using sampling valve, the light hydrocarbon emissions were captured in the exhaust manifold(catalyst before and after) and analyzed from LPLi engine exhaust manifold(catalyst before and after) using different fuel properties. Then exhaust samples were measured by gas chromatography(GC) and exhaust gas analyzer. Catalyst conversion efficiency for fuel properties of Butane 100% was better than Propane 100%. Start delay of LPLi engine was observed as increment of propane contents in LPG fuels.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.1011-1014
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• 1999

An on-board monitoring system for an automobile emission gas has a test chamber remote from the automobile's engine exhaust gas stream: apparatus for supplying the chamber with sampled exhaust gases. A single hydrocarbon sensor exposed to the exhaust gas in the chamber to render a signal responsive to the hydrocarbon. The conductive ions in emission gas was checked by the HC sensor in test chamber. A preferred application includes hydrocarbons in an automotive exhaust gas stream by exposing a transition porous alumina($Al_{2}O_{3}$) ceramic based sensor to the same exhaust gas stream. By combining the electrical signal, a measure of hydrocarbons can be provided.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.2 s.257
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• pp.167-172
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• 2007

A new method that optimizes a control of hydrocarbon (HC) addition to diesel exhaust gas for HC type DeNOx catalyst system has been developed. These catalysts are called the HC-DeHOx catalyst in this paper. The system using HC-DeNOx catalyst requires a resonable quantity of hydrocarbons addition in the inlet gas of the catalyst, because the HC concentration in a diesel engine is so low that the HC is not sufficient for NOx conversion. It is expected that this study offers a robust data developing HC injection system.

• Journal of Mechanical Science and Technology
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• v.14 no.10
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• pp.1168-1177
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• 2000

Hydrocarbon adsorber is considered as a promising technology to reduce cold start HCs in automotive exhaust gas. In this study, three in-line adsorber systems were tried to reduce the cold start emission. To check the basic characteristics of adsorber converters, surface areas, TPD and TP A were examined after a hydrothermal aging. Also idle engine bench was used to find the adsorption and desorption capabilities of the adsorber systems at cold start. Finally a practicability of the adsorber systems for the LEV achievement was checked with FTP test on a 2.0 D MIT vehicle. The results of this study indicate that hydrocarbon adsorber system is one of the promising passive technologies to meet the ULEV regulation.