• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1666-1671
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• 2004

In this study, a experimental method has been introduced for the various exhaust pipe geometry of 4-stroke single engine. The main experimental parameters are the variation of exhaust pipe diameters and lengths, to measuring the pulsating flow when the intake and exhaust valves are working, As the results of experimental test, the various exhaust geometry were influenced strongly on the exhaust pressure. As the exhaust pipe diameter was decreased, the amplitude and the number of compression wave in exhaust pressure was increased. According to decreasing pipe diameter, the number of compression wave in exhaust pressure was decreased. When the pipe diameter was increase, the second amplitude was increased.

• Journal of Power System Engineering
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• v.8 no.1
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• pp.13-17
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• 2004

In this study. an experimental study has been introduced for the various exhaust pipe geometry of 4-stroke single cylinder engine. The main experimental parameters are the variation of exhaust pipe diameters and lengths to measure the pulsating flow when the intake and exhaust valves are working. As the results of experimental test, the various exhaust geometry were influenced strongly on the exhaust pressure. As the exhaust pipe diameter was decreased, the amplitude and the number of compression wave in exhaust pressure was increased. According to decreasing pipe diameter, the number of compression wave in exhaust pressure was decreased.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.775-780
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• 2003

In this study, a computer analysis has been developed for predicting the pipe pressure of the intake and exhaust manifold in a single cylinder engine. To get the boundary conditions for a numerical analysis, one dimensional and unsteady gas dynamic calculation is performed by using the MOC(Method Of Characteristic). The main numerical parameters are the variation of the exhaust pipe diameters to calculate the pulsating flow when the intake and exhaust valves are working. As the results of numerical analysis, the shapes and distributions of the exhaust pipe pressures were influenced strongly on the cylinder pressure. As the exhaust pipe diameter is decreased, the amplitude of exhaust pressure is large and the cylinder pressure was showed low in the region of intake valve opening time.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.684-689
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• 2004

In this study, a experimental method has been introduced for the various exhaust pipe geometry of 4-stroke single cylinder engine. The main experimental parameters are the variation of exhaust pipe diameters and lengths, to measuring the pulsating flow when the intake and exhaust valves are working. As the results of experimental test, the various exhaust geometry were influenced strongly on the exhaust pressure. As the exhaust pipe diameter was decreased, the amplitude and the number of compression wave in exhaust pressure was increased. According to decreasing pipe diameter, the number of compression wave in exhaust pressure was decreased. When the pipe diameter was increase, the second amplitude was increased.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.3
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• pp.392-398
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• 1986

It is often occurred that exhaust pipe of an internal combustion engine should be bent due to some geometrical constraints. Especially for automobiles most of exhaust pipes of engines have curvature to avoid rear axles. In this paper effects of pipe curvature on the exhaust noise of a diesel engine have been studied experimentally. Experiments were carried out on a 4-cycle, 2164cc diesel engine. Two types of curvature, circular arc and retangle, were tested. Sound pressure level (SPL) and power spectrum of the exhaust noise were measured by inserting bent pipes of different curvature dimensions into the exhaust pipe at various engine operating conditions. The following results were obtained from this study. Among the engine operating conditions the exhaust noise was affected mainly by engine revolution speed. The noise was reduced by the circular arc bent pipe. The effectiveness of an arc bent pipe on the noise reduction was dominated by its arc angle and the maximum noise reduction was obtained by the angle of 180.deg.. But the noise reduction could not be obtained by the rectangular bent pipe, and at high engine speed the noise was rather increased due to turbulence of exhaust gas.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.6
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• pp.103-111
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• 2001

During cold-start period, the reduction of exhaust emissions is a challenging task. To decrease harmful gaseous substances such as HC, it is necessary to realize a fast catalyst warm-up. In this study, the performance of dual pipe exhaust system have been carried out through different test mode. From measurement of gas temperature and HC concentration, the following conclusions were derived ; 1) Compared with single pipe, dual pipe exhaust system remarkably increase temperature of exhaust gas going through M.C.C(Main Catalytic Converter). 2) W.C.C.(Warm-up Catalytic Converter) also decreases HC emission. To reduce HC emission, it is helpful to use W.C.C. as well as dual pipe exhaust system. 3) Using finite element method, it is shown that inner parts have much higher distribution of temperature than outer parts.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.1-6
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• 2009

The temperature of exhaust gas was raised by increasing of engine movement on developing engine. Thermal of high temperature and pressure reverse in bellows, because of increasing of engine movement and the thermal performance of converter in combustion. As a result, thermal loss is increased and thermal efficiency is decreased rapidly in bellows, it can occur to damage in mechanical structure. In this study, it was necessary to analyze back pressure performance and thermal characteristic on driving condition in exhaust system. It was adapted braid type bellows and straight type exhaust pipe. It was compared with curve type exhaust pipe for lay-out on considering to design of exhaust system. It was necessary to improve thermal characteristic and back pressure performance so that expansion cavity pipe(ECP) was installed between bellows and catalyst convert. Not only decreasing back pressure was solved but also thermal characteristic problems in exhaust pipe because of increasing capacity. According to this study, the basis of data is presented when new exhaust system is designed.

• Journal of Advanced Marine Engineering and Technology
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• v.28 no.1
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• pp.75-82
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• 2004

In this research, a computer analysis has been developed for predicting the Pipe pressure of the intake and exhaust manifold in a small single cylinder engine. To get the boundary conditions for a numerical analysis one dimensional and unsteady gas dynamic calculation is performed by using the MOC(Method Of Characteristics). The main numerical parameters are engine revolutions. to calculate the Pulsating flow which the intake and exhaust valves are working. The distributions of the exhaust pipe pressures were influenced strongly to the cylinder pressures and the shapes of exhaust pressure variation were similar to the Inside of cylinder pressure As the engine revolutions are increased. the intake pressure was lower than ambient pressure. The amplitude of exhaust pressure had increased and the phase of cylinder pressure $P_c$ is delayed and the amplitude of cylinder pressure were increased.

• Journal of the Korean Society of Safety
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• v.8 no.3
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• pp.3-12
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• 1993

In reciprocating internal combustion engine, engine performance Is greatly affected by volumetric efficiency. For gas flow, the dynamic effects caused by the pressure pulsation have influence on the volumetric efficiency and correlate to the configuration and pipe length of intake-exhaust system. In this study, the analytic investigation of the unstudy flow In exhaust pipe has been carried out by using the method of characteristics to predict volumetric efficiency. In conculusion, it is possible to take account of the exhaust pipe tuning effect in predicting the engine performance, by the analytic solution of the unsteady flow in the pipes, and comparision of prediction with experimental datas show a good agreement on the pressure varision in the exhaust pipe which has Influence on the volumetric efficiency and performance of engine.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.18 no.6
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• pp.69-75
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• 2019

In recent years, the driving performance and exhaust sound quality in automobiles have been recognized as important factors, as they maximize the driving fun to fulfil the demands of customers. Therefore, many automobile manufacturers are studying various exhaust pipe shapes to improve sound quality and optimize exhaust pressure. The objective of the exhaust pipe design is to maximize the engine efficiency using optimal exhaust pressure settings. In this study, an exhaust system was fabricated with different junction shapes, and the results were analyzed through various experiments. The exhaust gas pressure acting inside the exhaust pipe was measured using a pressure transducer. Meanwhile, the vibration generated in the vehicle was measured in three axial directions and analyzed. The ground noise generated in the indoor and outdoor of the vehicle was measured, and the noise generated at the maximum output was measured and analyzed.