http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
조장근(J.K. Cho),오상욱(S.W. Oh),박원규(W.G. Park),오세민(S.M. Oh),이수원(S.W. Lee) 한국전산유체공학회 1996 한국전산유체공학회 학술대회논문집 Vol.1996 No.-
The jet pump is being used in many fields for several purposes because of its simple construction and easy operation. The characteristics of the geometrical variables, pressure gradient and velocity distribution of the jet pump are studied using the CFD technique. The flow calculations through a bended nozzle, a mixing chamber and a venturi are presented and phenomenological aspects are discussed. This study solve 3-D steady incompressible Navier-Stokes equations using the Iterative time marching scheme. The governing equations are differenced with 1st-order accurate backward difference scheme for the time derivatives and 3rd-order accurate QUICK scheme for the convective terms, The Mark-and-cell concept was applied efficiently to solve continuity equation. which is differenced 2nd-order accurate central differenced scheme. The 4th-order artificial damping is added to the continuity equation for numerical stability. A O-type of grid system is generated inside a nozzle and venturi of the jet pump. It has concluded that the results of present study properly agree with physical flow phenomena.
우수한 기구학 특성을 가지는 새로운 병렬형 구형 3자유도 메커니즘의 구현
이석희(S. H. Lee),김희국(W. K. Kim),오세민(S. M. Oh),이병주(B. J. Yi) 한국정밀공학회 2004 한국정밀공학회 학술발표대회 논문집 Vol.2004 No.10월
In our pervious paper, a new parallel-type spherical 3-degree-of-freedom mechanism consisting of a two-degree-of-freedom parallel module and a serial RRR subchain was proposed[1]. In this paper, its improved version is suggested and implemented. Differently from the previous 3-dof spherical mechanism, gear chains are incorporated into the current version of the mechanism to drive the distal revolute joint of the serial subchain from the base of the mechanism and in fact, the modification significantly improves kinematic characteristics of the mechanism within its workspace. Firstly, after a brief description on its structure, the closed-form solutions of both the forward and the reverse position analysis are derived. Secondly, the first-order kinematic model of the mechanism for the inputs which are assumed to be located at the base is derived. Thirdly, through the simulations of the kinematic analysis via. kinematic isotropic index, it is confirmed that the mechanism has much more improved isotropic properties throughout the workspace of the mechanism than the previous mechanism in [1]. Lastly, the proposed mechanism is implemented to verify the results from this analysis.