• Journal of Power System Engineering
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• v.11 no.4
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• pp.5-11
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• 2007

본 연구는 SI기관 실린더 내의 유동장 변이 과정을 3차원 LDV 측정 기술을 사용하여 흡입과 압축과정 동안 정량적으로 분석하였다. 실험은 헤드에 각각 2개의 흡입밸브와 배기밸브를 갖는 기관이 모터링되는 공회전 상태에서 실시하였다. 지난 30년 동안 텀블과 스월은 실린더 내의 평균 유동 정량화에, 난류운동에너지는 난류 측정에 많이 사용되어 왔다. 그러나 텀블은 solid body 회전 유동을 비교하는데 적절하며, 서로 다른 유동 패턴 비교에는 부적절 하다는 것이 보고되고 있는 실정이다. 3차원 LDV시스템의 우수한 공간 분석 능력은 순간적인 유동장구조와 더불어 상대적으로 미세한 유동장의 구조 까지도 측정이 가능 하도록 하였다. 따라서 측정한 결과로부터 유동장의 난류운동에너지 등가면을 계산할 수 있었다. 본 실험 결과는 실린더 내의 난류 유동장 특성을 난류운동 에너지 등가면 정보를 이용하여 세심하게 관찰할 수 있음을 제시하고 있다.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.1
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• pp.92-99
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• 2006

The swirl ratio of a charge in the cylinder was estimated by calculating the ratio of the rotary speed of charge which could be simulated from the rotary speed of paddle in the swirl measurement apparatus, to the engine speed which could be calculated by measuring intake air flow rate. The automation of the swirl ratio measurement for cylinder head was achieved by controling both valve lift in cylinder head and a suction pressure of surge tank using two step-motors. The number of measurement position for calculating mean swirl ratio was varied by adjusting the interval of valve lift. The mean swirl ratio with varying the number of measurement position showed nearly constant value. Two measurement methods for measuring the swirl ratio were compared, one was to control the suction pressure of the surge tank with PID (proportional, integral, differential) mode with by-pass valve controlled by the step motor and the other did not control the surge tank pressure by fixing the by-pass valve. The difference of the mean swirl ratio between the two measurement methods showed nearly constant value with varying the number of measurement position. This means that the w/o PID control method could be preferred to the PID control method which has been used, due to the simpleness of the swirl measurement.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.790-795
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• 2001

Since the characteristics of combustion and pollutant in Diesel engines were mainly affected by the characteristics of in-cylinder gas flow and fuel spray, an understanding of those was essential to the design of the D.I. Diesel engines. The improvement of volumetric efficiency of air charging into combustion chamber is a primary requirement to obtain better mean effective pressure of an engine. Since the air resistances in intake and exhaust flow passages, valve lift and valve shape influence greatly to the volumetric efficiency, it is very important to investigate the flow characteristics of intake and exhaust port which develops air motion in the combustion chamber. This paper presents the results of an experimental investigation of steady flow through the various kinds of commercial cylinder head ports, and the development procedures of HHI's H21/32 prototype cylinder head ports.

• Tribology and Lubricants
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• v.27 no.2
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• pp.65-70
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• 2011

The power servo cylinder for driving accurately turbine stop valve of an atomic power plant is necessary to do turn-over owing to a leakage of oil and a structure problem, especially, it of a power plant be in demand a high quality standard depends entirely on import. There are much problem that the AlBC be to used as a material of piston head in cylinder are caused by wear. Therefore, it is necessary to examine friction characteristics of it. In this study, wear test experiments was carried out with AlBC and SCM440, using reciprocating friction tester of pin on disk. This result was shown that the wear mechanism of AlBC on working condition is adhesive wear and the maximum temperature of infra redray thermal image of frictional surface show over 2 mm from contact surface of pin and disk.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2003.05a
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• pp.118-122
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• 2003

본 연구를 시물레이션방법을 이용한 실린더 헤드라인 생산설비의 적정계획 및 성능산정을 위해 가용한 생산설비의 자료들로부터 요구되는 생산능력을 만족하는 생산설비를 구성한다. 구성된 설비들은 가용한 생산설비 운영조건을 고려한 가상의 시물레이션 모델로 구축하여 생산설비의 적정 구성 및 공정간의 재고 등을 산정한다. 시스템 성능 산정을 위해 본 연구에서는 AutoMod 시물레이터를 이용하여 실린더 헤드라인의 생산설비계획 문제에 적용한다. 본 연구는 다수의 생산설비를 이용한 설비계획 연구시 사전 분석과 능력산정 및 기존의 설비 운영 조건에 따른 생산능력산정에 유용할 수 있으며 3차원 동영상으로 분석 결과를 제시할 수 있다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.10a
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• pp.126-132
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• 1996

This study is pre-research to evaluate the reasonability of convertion aluminum alloy cylinder head cover into plastic cylinder head cover using finite element analysis. The basedata which are needed in design are shown. On processing the study size of mesh and kind of elements are varied and adaptiv method is used.

• Journal of Biosystems Engineering
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• v.6 no.2
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• pp.9-19
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• 1982

The aim of this study was to improve the startability of the diesel engine at low temperature. The specific objective was to determine the optimum type of precombustion chamber. The eight different types of precombustion chamber and two different types of the cylinder head were designed and tested by $2^7$ factorial experiments with four replications. The lowest starting temperature for first operation, the maximum output, and the specific fuel consumption at full load and overload were checked and analyzed. The results of the study are summarized as follows; 1. The lowest starting temperature was lowered as much as $2.4^{\circ}C$ and the maximum output was increased as much as 0.3 ps with respect to the difference in the relative angle of the main passageway against the piston head from 20 degree to 18 degree. 2. The lowest starting temperature and the maximum out-put were lowered as much as $3.3^{\circ}C$ and 0.3 ps respectively with respect to the difference in the angle of the cylinder head groove from 20 degree to 18 degree. 3. The lowest starting temperature and the maximum out put were lowered as much as $2^{\circ}C$ and 0.2 ps respectively with respect to the difference in the length of the precombustion chamber from 17.5 mm to 15.5mm. 4. There was no significant difference in the startability but the maximum output was increased as much as 0.2 ps with respect to the difference in the diameter of the main passageway from 4.8mm to 4.5mm. 5. The lowest starting temperature was obtained under the condition at 47 degree in the angle of the main passageway and at 18 degree in the angle of the cylinder head groove. The maximum output and the minimum specific fuel consumption was obtained under the condition at 4.5mm in the diameter of the main passageway and at 17.5mm in the length of the precombustion chamber. 6. The angle of the cylinder head groove and the main passageway appeared to the major factors affecting the startability significantly. The interaction between the diameter of the main pass ageway and the length of the precombustion chamber had an significant influence on the maximum output. So it would be recommended to study further on the interaction between two factors mentioned above by expanding their levels. 7. The optimum condition suggested by this study could lower the starting temperature by $6^{\circ}C$ compared to the conventional precombustion chambers.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.5
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• pp.178-187
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• 1997

For the experimental measurement of heat flux of DI diesel engine combustion chamber, the instantaneous temperature probes and data acquisition system were developed. By the analysis of measured temperatures at the cylinder head, the temperature at the point 3 which is located between intake and exhaust valve was higher than that of the other points. Temperatures at the point located mear the exhaust valve were higher than those of intake valve. The instantaneous and mean temperature at the cylinder head increases proportionally to the increase of the engine speed, while the temperature swing varies inversely. Temperature swings have influence on the maximum heat flux values from gas into head surface. It has been verified that these probes and data acquisition system perform well by the comparison of the trend of instantaneous temperature variation with that of measured combustion chamber pressure variation with respect to crank angle. It is presumed that these probes could be used in the measurement of other parts of combustion chamber as piston, cylinder wall etc. for the future study.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.806-811
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• 2001

Since the characteristics of combustion and pollutant in Diesel engines were mainly effected by the characteristics of in-cylinder gas flow and fuel spray, an understanding of those was essential to the design of the D.I. Diesel engines. The improvement of volumetric efficiency of air charging into combustion chamber is a primary requirement to obtain better mean effective pressure of an engine. Since parameters such as the air resistances in intake and exhaust flow passages, valve lift and valve shape influence greatly to the volumetric efficiency, it is very important to investigate the flow characteristics of intake and exhaust port which develops air motion in the combustion chamber. In this study, two approach methods were used for design intake and exhaust port; experiment and computation which were made by using steady flow test rig and commercial CFD code. This paper presents the results of an experimental and analytical investigation of steady flow through the prototype cylinder head ports and valves of the HHI's H21/32 HIMSEN Engine.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.321-325
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• 2000

Gasket of vehicle engine maintains airtight between cylinder head and engine block under high temperature and pressure, and plays important role in heat conduction of engine. And the characterization of the nonlinear behavior of metal gasket fer various bead shapes is very important as basic research for estimation of gasket durability. But it is very difficult to analyze the behavior of gasket In real experiment. In this paper, to analysis effects of the bead shape on the nonlinear behavior of cylinder head gasket under uniform pressure, the virtual experiment using the nonlinear finite element method was performed. Results are analyzed with residual deformation and the sealing pressure. With the increase of the height and the width of bead, the residual deformation and the sealing pressure increase. And if the height is very high and the width is very narrow, the wrinkles are occurred in the gasket while working.