http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 유영훈(Y.H. Yu) (검색결과 12 건)
- 무료
- 기관 내 무료
- 유료
-
코어공명을 이용한 허니콤패널의 흡음율 개선에 관한 연구
유영훈(Y.H. Yu) 한국동력기계공학회 2008 동력시스템공학회지 Vol.12 No.4
Honeycomb panel has a constructive advantage because it is constructed with a honeycomb core, so it has relatively higher strength ratio to weight. Therefore honeycomb panel has been used as the light weight panels in the high-speed railway technology and high-speed ship like as cruise yachts. Also it has been used in the aircraft and aerospace industry as a structural panel because light weight structure is indispensible in that field of industry. Recently, the honeycomb panel is embossed in the viewpoints of high oil prices as the lightweight panel of the transport machine, however the sound insulation capacity of the honeycomb panel is poorer than those of uniform and another sandwich panels. In this paper a method to improving the sound absorption coefficient of a honeycomb panel is studied by using the Helmholtz resonator. The sound absorption coefficients for some kinds of honeycomb cores are demonstrated by the normal incident absorption coefficient method.
-
-
-
-
-
선박기관실의 소음 저감을 위한 차폐공명기의 개발에 관한 연구
유영훈(Y. H. Yu) 한국동력기계공학회 2007 동력시스템공학회지 Vol.11 No.4
It is known that elimination of ship engine room noise is impossible thing, so the working environment in the engine room is getting worse because ships are recently built with huge engines to take higher sailing power. In the yacht and cruise yacht, the engine room noise is more serious because they have bigger engines relative to their hull sizes. The noise generated from the main engine makes the employee to hearing loss and the transmitted noise make the uncomfortable conditions in the cabins of ship. The noise generated by ship engine must be attenuate for the employee and passenger. In yacht and cruise yacht, the noise levels in cabines are the most important criterions to the value of commodities. In this study, the noise absorbtion barrier which have resonators is experimentally studied by the 1/3 octave band noise elimination rates(%).
-
유영훈(Y. H. Yu),양보석(B. S. Yang) 한국자동차공학회 1998 한국 자동차공학회논문집 Vol.6 No.2
The sound insulation capacity of honeycomb sandwich plates which have relatively higher strength ratios to weight is poorer than those of uniform and another sandwich plates. Therefore. improvement of the sound insulation capacity of the honeycomb sandwich plate which has a merit of lightness is required to use it in automobile and rapid rail road industries. In this study, to improving the sound insulation capacity of the honeycomb sandwich plate, the sound transmission loss of the structure is experimentally investigated by adding a viscoelastic damping layer. The effective add position and thickness of the layer were investigated from the viewpoints of both sound transmission<br/> loss and improved sound transmission loss over the frequency range from 800Hz to 10㎑
-
HART Ⅱ 로터-동체 모델의 CFD/CSD 연계해석과 동체효과 분석
사정환(J.H. Sa),유영현(Y.H. You),박재상(J.S. Park),박수형(S.H. Park),정성남(S.N. Jung),유영훈(Y.H. Yu) 한국전산유체공학회 2011 한국전산유체공학회 학술대회논문집 Vol.2011 No.5
A loosely coupling method is adopted to combine a computational fluid dynamics (CFD) solver and the comprehensive structural dynamics (CSD) code, CAMRAD Ⅱ, in a systematic manner to correlate the airloads, vortex trajectories, blade motions, and structural loads of the HART Ⅱ rotor in descending flight condition. A three-dimensional compressible Navier-Stokes solver, KFLOW, using chimera overlapped grids has been used to simulate unsteady flow phenomena over helicopter rotor blades. The number of grids used in the CFD computation is about 24 million for the isolated rotor and about 37.6 million for the rotor-fuselage configuration while keeping the background grid spacing identical as 10% blade chord length. The prediction of blade airloads is compared with the experimental data. The current method predicts reasonably well the BVI phenomena of blade airloads. The vortices generated from the fuselage have an influence on airloads in the 1st and 4th quadrants of rotor disk. It appeared that presence of the pylon cylinder resulted in complex turbulent flow field behind the hub center.
-
사정환(J.H. Sa),박수형(S.H. Park),김창주(C.-J. Kim),윤철용(C.Y. Yun),김승호(S.-H. Kim),김상호(S. Kim),유영훈(Y.H. Yu) 한국전산유체공학회 2009 한국전산유체공학회지 Vol.14 No.2
Numerical optimization of rotor blade airfoils is performed with a response surface method for helicopter rotor. For the baseline airfoils. OA 312, OA 309, and OA 407 airfoils are selected and optimized to improve aerodynamic performance. Aerodynamic coefficients required for the response surface method are obtained by using Navier-Stokes solver with k-w Shear Stress Transport turbulence model. An optimized airfoil has increased drag divergence Mach number. The present design optimization method can generate an optimized airfoil with multiple design constraints, whenever it is designed from different baseline airfoils at the same design condition.
-
ScienceON
DBpia연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
