간행물

한국기계기술학회지 KCI 등재 Journal of the Korean Society of Mechanical Technology 韓國機械技術學會誌

권호리스트/논문검색
이 간행물 논문 검색

권호

제10권 제3호 (2008년 9월) 6

학술연구

1.
2008.09 구독 인증기관 무료, 개인회원 유료
Resistance performances of a leisure yacht with different keels, which are center and double keels respectively, are investigated by model test at circulating water channel. Flow patterns around the keels are observed by tuft test to make clear the relation between resistance performance and flow around keels. The results show that the keel does not affect free surface and double keel yacht has better performance comparing single keel yacht in resistance point of view.
4,000원

생산기술

2.
2008.09 구독 인증기관 무료, 개인회원 유료
Filling liquid that wish to so that may dispensing to syringe of dispenser and dispensing because done pressure and time control and dispensing amount adjustment is depended on dispensing pressure, dispensing time and inside diameter of needle. Pressure that is supplied in syringe is regulated being proportional at open and shut time of high pressure of air regulator, low pressure adjustment and solenoid valve, and make and break of solenoid valve consists by existence point of contact and nothing point of contact switch. In this paper, automatic control system and process workers manufacture automatically work little more easily and conveniently, used syringe dispenser for column of water difference that use interactive algorithm way applicationintensity factor are presented and applied to several practical examples to demonstrate their accuracy.
4,000원

학술연구

3.
2008.09 구독 인증기관 무료, 개인회원 유료
본 연구는 여섯 개의 서로 다른 쉘로우 딤플(Shallow Dimple)에 의해 나타나는 유동구조 특성에 대한 연구결과을 기술하였다.(쉘로우 딤플(SD), 실린더 딤플(CD), 도우넛 딤플(DD), V자형 딤플(WD), 역방향 실린더 딤플(BCD), 역방향 V자형 딤플(BWD)). 딤플은 복잡하지 않은 제작절차를 비교적 요구하며 압력손실도 상대적으로 적으므로 사각 립(rectangular rib), 실린더와 같은 여러 가지 형상에 비해 열전달 손실을 줄이고 열전달 증대시키는 효과적인 장치이다. 본 연구결과을 통하여 여러 가지 딤플 형상에 따라 서로 다른 와류구조가 딤플의 중앙과 가장자리에서 생성, 발달, 소멸을 주기적으로 반복 발생되고 있음을 파악하였으며, 딤플의 중앙부위에서 와류가 발생할 때에는 서로 다른 딤플형상에서 7-9 Hz의 유사한 발산주기가 발생하였다. 또한, 압력손실정도를 파악하기 위한 마찰계수비는 최대 1.24, 최소 1.13으로 나타났으며 역방향 V자형 딤플이 가장 크고, 도우넛 딤플의 경우가 가장 적었다. 따라서, 서로 다른 딤플형상에서 발생되는 유동구조특성을 비교한 결과 쉘로우 딤플, 역방향 V자형 딤플 및 도우넛 딤플형상이 가장 큰 열전달을 증가시키는 것으로 나타났다.
4,000원

생산기술

4.
2008.09 구독 인증기관 무료, 개인회원 유료
An emergency diesel generator(EDG) manufactured by a French company Wartsila SACM is a tandem type engine and consisted of two 10 cylindered diesel engines on each side. The maintenance manual provided by the manufacturer recommends that engine bearing be inspected every 15 years. However, it is difficult to inspect them because the manhole located in the lower compartment of the engine is too small for maintenance worker to access engine internals. Furthermore, the EDG should be disassembled and then overturned to inspect bearings unlike other EDG type. Such process will take longer period time than ordinary maintenance period. So it is not possible to inspect the main engine bearing and crank shaft during a routine or scheduled maintenance. In this paper, five methods are proposed and estimated to resolve the problem and the optimal maintenance method is chosen among them. The proposed optimal maintenance plan makes it possible to perform proper maintenance during regular maintenance period and to lower maintenance cost considerably.
4,000원

학술연구

5.
2008.09 구독 인증기관 무료, 개인회원 유료
In a total hip arthroplasty, the artificial hip joint is composed of an acetabular cup and a femoral head. To minimize the wear of the joint, the bearing surface should be precisely spherical. There were concerns that the press-fitting of the acetabular cup to the pelvis may cause the deformation of the cup and accelerate the wear of the joint, but its in-vivo measurement was challenging. In this paper, 3 dimensional finite element(FE) models of a pelvis and acetabular cups of Metasul 50mm and Pinnacle 50-60mm cups were used to simulate the deformation of the acetabular cups. For Metasul cups, the change of inner radius with respect to the location and the maximum shrinkage of the inner radius were found. For the Pinnacle cups, maximum change of the outer diameter were found and compared with the literature. FE model showed that the maximum shrinkage of the inner radius of the Metasul cup was 23μm (1.0mm press-fit, Bone stiffness 17GPa case). The shrinkage occurred mainly on the anterior and posterior side of rim of the cup, and the amount was proportional to the press-fit amount. The diametric change of the Pinnacle cup was 0.16mm on average, which was in same range of the clinically reported value. In conclusion, under the normal condition the reduction of the inner radius of the Metasul cup was too small to cause the jamming or the excessive wear.
4,000원
6.
2008.09 구독 인증기관 무료, 개인회원 유료
In this paper, the effect of oxygen component in fuel on the exhaust emissions has been investigated for an indirect injection diesel engine. It was tested to estimate change of engine performance and exhaust emission characteristics for the commercial diesel fuel and oxygenate additive blended fuel which has four kinds of mixed ratio. Ethylene glycol mono butyl ether(EGBE) contains oxygen component 27% in itself, and it is a kind of effective oxygenated fuel of mono-ether group that the smoke emission of EGBE is reduced remarkably compared with commercial diesel fuel, that is, it can supply oxygen component sufficiently at higher loads in a IDI diesel engine.
4,000원