http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
장홍석(Hongsuk Chang),이중섭(Jungsup Lee) 한국자동차공학회 2012 한국자동차공학회 부문종합 학술대회 Vol.2012 No.5
Various optimization schemes have successfully been utilized to design mounting brackets of chassis components, especially suspension systems, in the large commercial vehicle development process. Depending on the design status, different optimization schemes, i.e. size, topology, and shape, are applied. There are two key elements that determine types of optimization schemes used, which are design freedom and available analysis time. First, in a case that the design is already frozen near the mass production, so that only minimal design change and time is allowed, the size optimization is attempted. Second, in the middle of the design process where relatively more room for the change is available, the topology optimization is adequate to carry out, based on the basic CAD model. Finally, early in the design process, when total freedom is given for the design and sufficient analysis time is allowed, both the topology and the shape optimization can be adopted, starting from a box model without any reference CAD model. In this paper, it is discussed how these optimization methods were exploited to achieve an optimized design of the brackets ? more stiffness, strength, and less weight. As a example, hanger mounting bracket is optimized by using suggested well-developed optimization process.
장홍석(Hongsuk Chang) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_3
Various optimization schemes have successfully been utilized to design the mounting brackets of the chassis components, especially suspension systems, recently in the heavy duty truck development process. Depending on the design status, different optimization schemes, i.e. size, topology, and shape, are applied. First, in case that the design is already frozen near the mass production, so that only minimal change is allowed, the size optimization is attempted. Second, in the middle of the design process where relatively a more room for the change is available, the shape optimization is adequate to carry out, based on the basic CAD model. Finally, early in the design process, when a total freedom is given for the design, the topology optimization can be adopted, starting from a box model without any reference CAD model. In this paper, it is discussed how these optimization methods were exploited to achieve an optimized design of the brackets - more stiffness, strength, and less weight.
장홍석(Chang Hong Suk),유승원(Yoo Seung Won),박종찬(Park, Jong Chan) 대한기계학회 2015 大韓機械學會論文集A Vol.39 No.3
차량 경량화가 진행되고 있는 요즈음 상용차의 프레임이나 데크를 일반강에서 고장력강으로 대체하고 있는 상황이다. 일반강의 용접부 내구 특성에 대한 연구는 지금까지 많이 이루어졌으나 고장력강 용접부에 대한 연구는 거의 진행되지 않았다. 본 연구에선 첫째, 상용차량에 적합한 용접부 내구를 예측기법을 찾기 위해 다수의 접근법을 검토해 보았으며 노치계수 접근법인 Radaj 방법을 선택하였다. 둘째, 오버랩 조인트와 T 조인트 용접시편을 이용한 내구시험을 통해서 F-N 선도를 얻었으며, 이 값을 활용하여 HARDOX, ATOS60 재질에 대한 S-N 선도를 추출할 수 있었다. 셋째, 노치계수 접근법을 사용하여 시편 시험으로 얻어진 F-N 선도를 활용하여 고장력강 용접부의 일반적인 S-N 선도를 구할 수 있었다. 넷째, 연구를 통해 얻어진 고장력강 용접부의 내구특성을 상용내구해석 프로그램에 적용하였다. 마지막으로 해석사례를 통해 시험과 해석결과를 비교하였으며, 신뢰할만한 결과를 얻을 수 있었다. High-strength steel has replaced mild steel as the material of choice for truck decks or frames, owing to the growing demand for lightweight vehicles. Although studies on the weld fatigue characteristics of mild steel are available, studies on high-strength steels have been seldom conducted. In this study, firstly, we surveyed a chosen number of approaches and selected the Radaj method, which uses the notch factor approach, as the one suitable for evaluating the fatigue life of commercial vehicles. Secondly, we obtained the S-N curves of HARDOX and ATOS60 steel welds, and the F-N curves of the T-weld and overlapped-weld structures. Thirdly, we acquired a general S-N curve of welded structures made of high-strength steel from the F-N curve, using the notch factor approach. Fourthly, we extracted the weld fatigue characteristics of high-strength steel and incorporated the results in the database of a commercial fatigue program . Finally, we compared the results of the fatigue test and the CAE prediction of the example case, which demonstrated sufficiently good agreement.