• Journal of the Korean Society for Precision Engineering
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• v.28 no.2
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• pp.185-192
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• 2011

This study deals with a basic proposal to prove the safety for the exhausted fittings of the hydrogen fuel cell vehicle. First, this study was approached to numerical analysis solving to close the exact boundary condition (Axial, Bending, Lateral) and the second, this study produced the Lateral movement equipment for the vibration. For the numerical analysis, This study was considered with the exact solution of Lateral movement and the resonance effect for durability sample according to fitting positions. The second, This study was made for special equipment for displacement/gas leak and the frequency because the domestic samples were comparing with foreign fitting and foreign fitting for the hydrogen fuel cell vehicle. The result of this study was satisfied with domestic fittings for the basic reference but it need more test because of other situation for hydrogen fuel cell vehicle.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.02a
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• pp.171-177
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• 2000

• Journal of the korean Society of Automotive Engineers
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• v.14 no.6
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• pp.48-59
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• 1992

This study is on the performance of the perforated tube muffler when it operates as an exhaust silencer with through-flow, steady or pulsating. Theoretical estimation of the insertion loss was made by means of transfer matrix and by using the impedance equation for the perforated tube obtained for the case of low-speed steady through-flow. Experiment was performed for the measurement of the insertion loss at two flow conditions. The one is a steady flow from the exhaust pipe of an idling diesel engine. The effect of the through-flow velocity and steadiness on the muffler performance was obtained. By comparing the theoretical prediction with the experimental result, the validity of the impedance equation in the theoretical model was discussed. It has been found that steadiness as well as magnitude of the through-flow has a significant effect on the performance of the perforated tube muffler. Especially, the self-noise due to the pulsating flow in the engine exhaust system must be taken into account for the prediction of the muffler performance.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.5
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• pp.42-51
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• 2000

The performances of the simple expansion, perforated tube, and conical-connector type as an exhaust muffler are shown in this study. Applying a model in which the method of four-pole parameter is used makes theoretical estimation of the insertion loss. Experiment is performed for the measurement of the insertion loss under four cases according to the variation of the tail pipe length. By comparing the theoretical prediction with the experimental results, the validity of the modeling using the method of four-pole parameter is verified. The personal computer simulation programs for the above mentioned theory on the muffler design have been developed and exhaust sound level measurements have been carried out for simple expansion muffler, conical-connector muffler, perforated tube mufflers and the combined type of conical-connector and simple expansion muffler. The measured results for attenuation characteristics of noise for each muffler are compared with the computed theoretical results to verity the confidence and applicable limits of the theoretical equation derived.

• 한국연소학회:학술대회논문집
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• 2012.04a
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• pp.151-152
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• 2012

Collectors connected to diesel engine exhaust pipe for application of PM reduction facilities which was used to reduce PM from the exhaust gas produced from ship, Filtration performance of PM was tested. In this system, it was confirmed that the bag house can remove over 90 percent of PM from a lot of high temperature and high pressure gases produced in diesel engine. The results obtained from performance test show the potential possibility for commercialization of ceramic filter collectors which is applied to reduction facilities of flue gas produced from a diesel engine on the ship.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.6
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• pp.72-81
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• 1991

In this study, the analytic investigation of the unsteady flow in the intake and exhaust pipes has been carried out using the method of characteristics in one direction to predict volumetric efficiency. Based on the calculated volumetric efficiency, three zone predictive analysis using Wiebe function was applied to predict the engine performance and the results were compared with experiment. Mixture in the cylinder is subdivided into three zones during combustion process in this analysis; adiabatic core zone, thermal boundary layer zone and unburned zone. In each zone, pressure, temperature and gas composition have been calculated. In conclusion, it is possible to take account of the intake and exhaust pipe tuning effect in predicting the engine performance, by the analytic solution of the unsteady flow in the pipes, and comparison of prediction with experimental results shows a good agreement on the pressure variation in the intake and exhaust pipes which has a direct influence on the volumetric efficiency and performance of the engine.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.6
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• pp.85-91
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• 1988

The purpose of this study is to investigate the flow through the intake and exhaust system of a spark ignition engine. The flow was assumed to be one-dimensional, compressible and unsteady, and carburetor, muffler, valve and junction are modelled as boundary conditions according to their flow characteristics. In the experiment, four cylinder gasoline engine is used and the pressures in the intake and exhaust pipes and in the cylinder are measured and compared with the results of numerical analysis. In consequence of the comparison, four periods of pressure wave in a cycle are observed in both case of experiment and prediction. In case of exhaust pipe, the results obtained from the experiment are in accord with that from calculation. The results of the intake system show some differences with each other due to the complication in shape, but the periods of both case concur well.

• Journal of the Semiconductor & Display Technology
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• v.6 no.1 s.18
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• pp.59-64
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• 2007

Non-contact transportation of a large-sized glass plate using air cushion for the vertical sputtering system of liquid crystal display (LCD) panel was considered. The objective of the study was to design an air pad unit which was composed of multiple injection and exhaust holes and mass flow supplying pipe. The gas was injected through multiple small holes to maintain the force for levitating glass plate. After hitting the plate, the air was vented through exhaust holes. Complex flow field and resulting pressure distribution on the glass surface were numerically studied to design the air injection pad. The exhaust hole size was varied to obtain evenly distributed pressure distribution at fixed diameter of the injection hole. Considering the force for levitating glass plate, the diameter of the exhaust hole of 30 to 40 times of the gas injection hole was recommended.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.2
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• pp.121-127
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• 2011

NOx (Nitrogen Oxide) reduction system periodically needs a rich or stoichiometric operating condition to reduce NOx. A new method that optimizes the control of external HC injection into a diesel exhaust pipe for HC-type LNT (Lean NOx Trap) catalyst system has been developed. In this paper, these catalysts are called HC-LNT catalysts. The concentration and amount of HC can be controlled by controlling the external injection. In this study, we investigated the relationship between the spray behavior of hydrocarbons injected into the transparent exhaust pipe and NOx reduction characteristics. From the results of this experiment, we obtained useful information about the optimum injection and position of HC injector to the exhaust pipe. Further, we obtained useful information about the optimal injection condition for an HC-LNT catalyst system with a gasoline PFI (port fuel injection) typeinjector.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.6
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• pp.53-59
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• 1987

The effect of the three types of fuel vaporizing device on the engine torque and exhaust emission was investigated. Among the three types of fuel vaporizing device designed for the experiments, a 88mm long device with mesh around the inside pipe showed stable lean mixture combustion up to 21:1 air-fuel ratio and reduced the exhaustion of CO and HC. Compared with the general trend in the decrease of engine torque it was observed that the decrease of engine torque in this lean mixture combustion with the new device was small.