http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
이상승(S. Lee),김명균(M. Kim),유동현(D. You),김정재(J.J. Kim),이상준(S.J. Lee) 한국전산유체공학회 2016 한국전산유체공학회지 Vol.21 No.1
In order to investigate effects of grid resolution on large-eddy simulation of flow over a heavy vehicle, large-eddy simulations over the vehicle with coarse grid and fine grid are conducted. In addition, comparison of drag coefficients with the experimental data obtained by a wind tunnel experiment is conducted. Both of the drag coefficients of coarse grid and fine grid large-eddy simulation show good agreement with the experimental data. Flow fields obtained by the coarse and the fine grid large-eddy simulation are compared in the vehicle frontal-face region, the vehicle rear wheel region, and the vehicle base region. Coarse grid large-eddy simulation shows good agreement with the fine grid large-eddy simulation in the vehicle front face region and the vehicle rear wheel region, since the flow over the present vehicle is dominated by flow separation which is geometrically pre-determined, not by the skin friction which is known to be sensitive to grid resolution.
[가솔린엔진] 밸브벽면과 제트의 부착효과로 인한 질량유량 감소에 관한 연구
이준서(J.S. Lee),김명균(M.K. Kim),차경옥(K.O. Cha) 한국자동차공학회 1999 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
Flow characteristics of a compressible gas flow through a rotating disc-type rotary valve are investigated experimentally under various conditions. It is known that the mass flow rate through poppet valves of 4-stroke cycle engines and through piston valves of 2-stroke cycle engines decrease with increase in engine speed. Rotary valve is one means by which air may be made to flow intermittently through a pipe. In this paper an exhaust system simulator of engine was used to experimentally analyze the decrease in flow rate at high rotation speeds and to determine what variables. other than rotational speed. give rise to the observed behaviour. These variables have been included in an empirical equation which is representative of the measured flow characteristics.