http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
엔진 밸브 융착부의 잔류 응력 최적화 공법에 대한 연구
한상민(Sangmin Han),홍재웅(Jaewoong Hong),오재욱(Jaeook Oh),김현승(Hyunseung Kim),이경태(Kyoungtae Lee) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5
Many gaseous fuel (LPG and CNG) engines are being developed due to economic efficiency compared with gasoline engines. Wear-resistant material development of engine valves and valve seat insert (VSI) is important for the gaseous engine development. The use of gaseous fuels often result in significant increases valve seat insert (VSI) wear and valve seat wear due to the lack of the lubricity of the fuel. The hardened materials are adapted for valve seat insert (VSI) and welded valve seat material. The heavy wear and thermal/mechanical impact can make cracks in welded valve in the last of engine endurance test. The brittleness of hardening material and residual stress made by welding are also reasons of valve cracks. Developments of valve welding material and valve seat insert material (VSI), welding quality and heat treatment process after welding are required for increased gaseous engine life. In this study, the measurement method of residual hoop stress was developed for welded valve head. The optimized control factors in post weld heat treatment are defined without any negative side effect using DFSS process. The selected control factors have to be more robust factors for noise. After finding the effects of control factors on optimized heat treatment using DFSS process, Negative side effects are investigated. Finally the improved fatigue characteristics of welded valve are validated with real engine dynamometer endurance test.
디젤 엔진 실린더 헤드의 워터 재킷 표면의 온도가 침식 및 부식에 미치는 영향
황준식(Joonsik Hwang),김동훈(Donghoon Kim),한상욱(Sangwook Han),배충식(Choongsik Bae),홍재웅(Jaewoong Hong),윤수환(Soohwan Yoon) 한국자동차공학회 2012 한국자동차공학회 학술대회 및 전시회 Vol.2012 No.11
In recent years, there have been reports of erosion on cylinder head water jacket from several vehicle manufacturers. The degree of erosion may cause deterioration in the cooling capabilities and serious damage to the engine. The reason for the erosion is widely known as repeating formation and collapse of bubble caused by temperature difference between coolant and surface temperature. Therefore, in this study, the erosion and corrosion behavior of water jacket was investigated with rectangular specimen under 3 different specimen temperature conditions (170℃, 200℃, 230℃). The experiment was conducted in test bench which provide the similar conditions as diesel engine cylinder head. The surface of specimen was visualized with SEM-images after 25hours of operation in the test bench and the weight was measured with precise mass scale. The surface composition of specimen which was exposed to coolant during the experiment was quantified with energy dispersive spectroscopy (EDS) analysis every 25hours in the experiment. From the results, the greatest differential rate of mass reductions were observed with highest surface temperature (230℃) experiment. The composition of aluminum and silicon on the specimen did not have clearly consistent tendency.
CO₂규제 대응을 위한 고출력 2.0 Liter EURO-V 디젤엔진 개발
이해성(Haesung Lee),오재욱(Jaeook Oh),김승철(Seungcheol Kim),홍재웅(Jaewoong Hong) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5
As environmental awareness is growing over the world considerably, GM Korea has developed a new 2.0L high torque Turbocharged Diesel engine to comply with Euro5 emission regulations and CO2 reduction requirement, for installation in SUV, MY2012 program. The development concept is focused on CO2 reduction, high performance, NVH improvement, reliability, and emissions in compliance with Euro5 standards. This paper presents an overview of this newly developed Diesel engine and explains the technical choices made in accordance with design and cost constraints.
실린더 헤드 워터 재킷 표면 조건이 침식에 미치는 영향
이민석(Minseok Lee),황준식(Joonsik Hwang),김동훈(Donghoon Kim),한상욱(Sangwook Han),배충식(Choongsik Bae),홍재웅(Jaewoong Hong),윤수환(Soohwan Yoon),신상연(Sangyeon Shin) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10
The occurrence of erosion on cylinder head water jacket recently has been reported from some vehicle manufacturers and it may cause deterioration of cooling capability and serious damages to the engine. Therefore, in this study, the erosion behavior of A356 aluminum alloy which consists cylinder head water jacket was investigated with rectangular specimen under various surface conditions. The experiment was conducted in the test bench which simulates cylinder head water jacket. The surface of specimen was analyzed with scanning electron microscopy(SEM) after 10 hours of operation in the test bench and weighted by precise mass balance. The surface composition of specimen also was quantified with energy dispersive spectroscopy(EDS) analysis. The results showed that the dominant factor affecting erosion was the temperature of specimen.