• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.2
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• pp.63-68
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• 2003

The purpose of this study was to investigate reduction of exhaust gas temperature in LPG conversion engine from diesel. A conventional diesel engine was modified to a LPG(Liquified Petroleum Gas) engine that diesel fuel injection pump was replaced by the LPG fuel system. The research was peformed with measurement of exhaust gas temperature by varying spark ignition timing, air-fuel ratio, compression ratio, EGR ratio and different compositions of butane and propane. The major conclusion of this work were followed. (i) Exhaust gas temperature was decreased and power was increased with the advanced spark ignition timing. (ii) Exhaust gas temperature was decreased with lean and rich air-fuel ratio. (iii)Exhaust gas temperature was decreased and power was increased with the higher compression ratio. (iv) Engine power and exhaust temperature were not influenced by varied butane/propane fuel compositions. (v) Finally, one of the important parameters in reduction of exhaust gas temperature is spark ignition timing among the parameters in this study.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.3 s.234
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• pp.384-389
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• 2005

Experimental study of variation of exhaust gas temperature was carried out with the changes of spark timing and exhaust valve timing during the cold start operation of an SI engine. To investigate the effects of these variables on combustion stability, cylinder pressure and exhaust gas temperature were measured and analyzed. Experimental results showed that exhaust gas temperature increased when spark and exhaust valve timings were retarded from the baseline cases. However, combustion stability during cold start deteriorated under the retarded conditions. To increase exhaust gas temperature for fast warmup of catalysts while maintaining combustion stability, an optimal condition for spark and valve timing retard should be appied for the cold start period.

• International Journal of Automotive Technology
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• v.6 no.6
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• pp.585-590
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• 2005

The effects of spark timing and exhaust valve timing change on exhaust gas temperature during cold start period of an SI engine are studied through engine bench tests. The exhaust gas temperature increases when the spark timing or valve timing are retarded individually, due to late combustion or slow flame speed. Therefore, exhaust gas temperature shows a large increase when the two timings are retarded simultaneously. However, it is considered that combustion stability during cold start deteriorated under these retarded conditions. To increase exhaust gas temperature for fast warmup of catalysts while maintaining combustion stability, an optimal condition for spark and valve timing retard should be applied for the cold start period.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.8
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• pp.597-603
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• 2008

The catalyzed diesel particulate filter (CDPF) is widely used for collecting soot from the exhaust gas of diesel engine. However, the CDPF need being regenerated after the soot accumulation. It is important to know characteristics of regeneration for CDPF with variation of exhaust gas temperature and composition. This study presents characteristics of regeneration according to variable exhaust gas composition. Furthermore, the experiment were performed variable gas temperature of CDPF inlet gas at each exhaust gas composition. Test-rig is used to control at each in let gas temperature and composition during regeneration of CDPF. Reaction intensity($I_c$) is used to compare with each result. Experimental results indicated that increased concentration of $NO_x$ and $O_2$ lead to regenerate more greatly. Also, higher temperature of exhaust gas leads to make CDPF cleaner.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.2
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• pp.9-16
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• 2004

Close-coupled catalyst (CCC) can reduce the engine cold-start emissions by utilizing the energy in the exhaust gas. However, in case the engine is operated at high engine speed and load condition, the catalytic converter may be damaged and eventually deactivated by thermal aging. Excess fuel is sometimes supplied intentionally to lower the exhaust gas temperature avoiding the thermal aging. This sacrifices the fuel economy and exhaust emissions. This paper describes the results of an exhaust heat exchanger to lower the exhaust gas temperature mainly under high load conditions. The heat exchanger was installed between the exhaust manifold and the inlet of close-coupled catalytic converter. The exhaust heat exchanger successfully decreased the exhaust gas temperature, which eliminated the requirement of fuel enrichment under high load conditions. However, the cooling of the exhaust gas through the heat exchanger may cause the deterioration of exhaust emissions at cold start due to the increment of catalyst light-off time.

• Journal of ILASS-Korea
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• v.23 no.4
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• pp.221-226
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• 2018

Despite the increasingly stringent automotive emissions regulations, the impact of vehicle emissions on air pollution remains large. In addition, since the issue of emission of more exhaust gas than the exhaust gas measured in the test room when the vehicle passing the exhaust gas regulation standard is run on the actual road, many countries studied and introduced gas regulations about Real Driving Emission using Portable Emission Measurement System. At present, Korea regulations restrict the number of NOx and PN in diesel vehicles. In the case of gasoline vehicles, there is no regulation on emission gas, but there is a problem of continuing automobile exhaust gas problems and a large amount of gasoline GDI vehicle's PN emission. So research and interest are increasing due to this problem. In this study, characteristics of exhaust gas depending on changes of ambient temperature were analyzed among various factors affecting exhaust gas measurement of gasoline vehicles. As a result, at the low temperature test, the lower the ambient temperature, the more the exhaust gas was emitted. At ordinary temperature test, no specific tendency was observed due to changes of ambient temperature.

• Journal of ILASS-Korea
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• v.9 no.1
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• pp.15-20
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• 2004

The post injection effect to enhance aftertreatment devices' performance is essential to meet future stringent emission standards by controlling exhaust gas temperature and emission pollutants. The test has been made with commercial common rail diesel engine by post injection manipulation, to optimize exhaust gas temperature while guarantee low fuel penalty. The optimization was done at 1500, 2000 and 2500[rpm] for 2, 4[bar] condition which show low exhaust gas temperature. The main purpose of this test is dedicated to understand mechanism of exhaust gas temperature rise while optimizing

• Journal of the Korean Society of Mechanical Technology
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• v.13 no.2
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• pp.55-61
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• 2011

This study analyzed on the characteristics of temperature distribution in an active regeneration DPF using computer simulation. In order to verify the boundary condition of analysis, results of temperature distribution in DPF are compared between experimental and computer simulation. Using this boundary condition, temperature distribution and filter's durability in DPF analyzed according to various operating conditions. The results of computational analysis are agreed well with experimental ones from the tendency of temperature distribution of axis and radius direction. The temperature increases and the axial temperature gradients in DPF according to velocity of exhaust gas are lowered as the high velocity of exhaust gas. But the temperature gradients of radius direction at exit side in DPF are grown as the high velocity of exhaust gas. The results according to inlet temperature of exhaust gas show that the increase ratios of temperature in DPF are grown as the high temperature of exhaust gas.

• Journal of Power System Engineering
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• v.19 no.6
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• pp.47-53
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• 2015

Korea is the geographic location during the summer, the temperature rising to $35^{\circ}C$ and winter temperature is $-15^{\circ}C$ to reduce the air temperature changes, such as relatively large compared to other countries. This increase or decrease of the harmful exhaust gas discharged from automobile substantially inconvenience a significant impact on the active side of the car engine temperature and exhaust gas reducing device receives a large impact on the atmospheric temperature is regulation to be different. However, domestic vehicle emissions test temperature of $20{\sim}30^{\circ}C$ is it does not reflect this situation the actual test temperature to accurately measure the exhaust gas volume of the vehicle is difficult. In this study, domestic automobile exhaust gas test conditions of a test temperature $20{\sim}30^{\circ}C$ various temperatures, including (35, 25, 0, -7, -15, $-25^{\circ}C$) under the two vehicles (2.0L MPI, 2.4 L GDI) as was discussed with respect to the exhaust gas characteristics of the vehicle according to the ambient temperature gas. As a result, domestic emissions test temperature of $25^{\circ}C$ than average conditions were temperature decreases greenhouse gas emissions and increase overall increased by up to 15 times higher. Air temperature and the engine exhaust gas inconvenience a direct effect on the activation temperature required in the reduction unit is determined to be an increase of emissions and greenhouse gases, and also an increase in the variety of lubricants based lubricating and viscosity reduction, such as the engine oil due to the low temperature of these result It is considered that shows the.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.60-64
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• 2000

An experimental study was performed to investigate the optimal ejector and operating condition of vessel incinerator. Exhaust gas temperature and secondary air which makes vacuum pressure at ejector throat regions were considered as an important factor. According to the measurement of pressure temperature and nitrogen oxides between non combustion and combustion we found the stream and exhaust gas characteristics of incinerator. This results can give us the exhaust gas temperature control system air pollutant reduction method and the optimum ejector design.