• 오토저널
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• 제7권4호
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• pp.9-17
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• 1985

엔진이 고성능화가 되어감에 따라 실린더 헤드 가스켓 재료나 밀봉(sealing) 구조가 계속해서 변 천되어 가고 있고 이는 엔진의 성능향상이 헤드 가스켓에 의해 크게 좌우된다는 것을 알려준다. 그러나 종래에는 헤드와 엔진보아(bore) 간의 밀봉문제가 가스켓만의 문제로 해서 검토하는 경우 가 많았다. 거기에다 검토 되어지는 것도 엔진의 개발 최종단계에서 이기 때문에 엔진을 개선할 수 없어 여러 가지 문제점을 가스켓이 부담하는 경우가 많았다. 그에 의한 무리한 대책은 나중 에 여러 가지 문제를 야기하는 결과를 가져다 준다. 그래서 여기서는 실린더 헤드 가스켓에 관 한 전반적인 내용을 서술하고자 한다.

• 오토저널
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• 제8권1호
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• pp.5-13
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• 1986

내연기관... 1. 헤드가스켓과 엔진구조의 관계 2. 유지(Maintenance)와 헤드볼트 축력관리 3. 헤드가스켓 설계

• 한국자동차공학회논문집
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• 제4권5호
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• pp.197-205
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• 1996

The flow characteristics of five different 4-valve cylinder heads were investigated in a steady flow rig using laser-Doppler velocimetry. The tumble flow of each head with pentroof combustion chamber was quantified by nondimensional tumble number using a tumble adaptor. The formation of tumbling vortex was examined in an optical single-cylinder engine which has windows for in-cylinder LDV measurements. Tumble vortex ratio was estimated from the tumble flow measurement. The four-valve cylinder heads with pent-roof combustion chamber showed the tumble vortex from the intake process, which was investigated in the steady flow test. The tumble adaptor which converts the tumble into swirl flow was found to be feasible in predicting the tumble flow in the real engine. The tumble strength in the steady flow test coincides with that in the real engine experiment within 15%. It was found that the steady flow test on the four-valve cylinder heads provides the tip for a better design of cylinder head.

• 한국공작기계학회논문집
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• 제13권6호
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• pp.81-86
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• 2004

Generally, automotive cylinder head is manufactured by FCD45 material that is hard to cutting materials, and it needs the accurate machining tool fir higher output of engine. This paper is concerned with a study on TiN coated 6 edges reamer for improving machining accuracy of cylinder head guide pin. The reamer shape is changed from 4 edges to 6 edges for the improvement of machining accuracy. Also, TiN coating is applied to the improvement of surface roughness of cylinder head guide pin and tool life of 6 edges reamer. It is noted that 6 edges reamer are effective in controlling the dimensional accuracy and surface roughness as well as increasing tool life.

• 한국자동차공학회논문집
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• 제7권5호
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• pp.89-95
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• 1999

In this study, the corrosion resistance of the aluminum casting commercial materials used in the automotive engine parts with respect to the anti-freeze coolant environment has been tested by the potentio dynamic method. especially, the effect of borax additive in engine coolant on the corrosion resistance of the aluminum casting materials has been evaluated. It was found that the borax in commercial engine coolant, used to prevent the corrosion in cast iron engine, causes a pit corrosion of aluminum casting materials at high temperature. During the engine endurance test with the coolant containing borax, the aluminum cylinder head was failed by the pitting corrosion near the exhaust port. Conclusively, it was suggested that the use of borax in the anti-freeze coolant be restricted for the automotive with aluminum cylinder head.

• 한국가스학회지
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• 제25권2호
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• pp.22-27
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• 2021

이 논문은 LPG 자동차용 엔진의 고장사례를 연구하여 자동차 생산에 활용함이 목적이다. 첫번째 사례는 엔진의 실린더헤드를 분해하여 확인한 결과 실린더 헤드의 점화플러그가 조립되는 나사부 마멸때문에 점화플러그의 불꽃이 누설되어 출력이 떨어지면서 엔진의 부조화 현상이 가끔 유발되는 것을 발견하였다.. 두 번째 사례는 캠샤프트의 위치와 크랭크 샤프트 위치를 맞춘 타이밍 마크가 0.5칸 틀어져 엔진의 부조화 현상이 발생된 것을 확인되었다. 세 번째 사례는 실린더 헤드를 분해하여 확인한 결과, 실린더 헤드에 제거되지 못한 이물질이 3번 흡기포트에서 공기 흐름에 따라 이동하다가 흡기밸브의 닫힘시기를 원활하지 못하여 하여 고장이 발생된 것을 확인하였다. 따라서, 자동차 관리자는 철저하게 점검해야 하고, 자동차 생산자는 철저한 품질확보를 통해 고장의 원인을 제거해야 할 것으로 판단된다.

• 한국자동차공학회논문집
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• 제11권3호
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• pp.28-38
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• 2003

Finite element analysis of cylinder heat/block compound under assembly, thermal and firing condition were performed. FE model including two cylinders with gasket, head bolts, liners and valve seats was used. FE modeling method and boundary conditions were introduced. Stress distribution and deformation of cylinder head and block under each loading condition were presented. Gasket pressure distribution and bore distortion level were predicted. Measured data of bore distortion was compared with the analysis results. The analysis result showed similar trends with the experimental data. High cycle fatigue analysis on the basis of this result has been performed in order to find the critical areas of the engine assembly.

• 한국자동차공학회논문집
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• 제19권6호
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• pp.133-139
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• 2011

Maintaining adequate sealing in engine cylinder head is a crucial factor in engine design. Failure of engine operations occurs mainly owing to the leaking by decreased sealing pressure. Reliability-robustness concept is applied to the engine cylinder head system. Deterministic way to obtain engineering solution in CAE industry may not consider the effects of noises and disturbances experienced during operation. However, analytical reliability-robustness concept may make possible to reduce the sensitivity of system with noise factors. Influences of design factors including noise factors would be predicted in analytical way. Optimized design may be obtained by shrinking variability and shifting to design target. Three-dimensional finite element analyses have been performed to apply analytical reliability-robustness concept.

• 한국자동차공학회논문집
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• 제10권6호
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• pp.1-10
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• 2002

As the preliminary stage for the countermeasure of thermal loading in miller cycle engine, coolant flows in the cylinder head of base engine including exhaust valve bridge were visualized and analyzed by using PIV technique. It was found that low coolant velocity regions were around exhaust valve bridge, around which stagnation of the coolant flow was observed due to the complex geometry configuration of water jacket. And velocity variation between each cylinder was remarkable. For the countermeasure of these, it is necessary to enhance coolant flow around exhaust valve bridge and to improve the deviation of coolant flow between each cylinder.

• 한국자동차공학회논문집
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• 제8권5호
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• pp.121-128
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• 2000

Simple design methods were developed to control the coolant flow rates through cylinder head gasket holes. Applying the concept of flow through an obstruction the ratio of intake to exhaust side flow rates could be easily controlled while maintaining the flow rates per cylinder of the original model. Flow distribution in the coolant passage of the original model was calculated by CFD and the flow rates at the gasket holes were modified based on the calculation results. The calculated flow rated of the modified gasket holes were reasonably close to target values. For more accurate control of the flow rate distribution, a design method with iterative CFD calculations was also suggested. The final size of gasket holes for the target flow rates were obtained just after a few optimization iterations. These methods can be very useful for the optimization of heat transfer characteristics in engine cylinder head and block.