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 : 왕지석(J. S. Wang) (검색결과 6 건)
- 무료
- 기관 내 무료
- 유료
-
-
허일,왕지석,Hur, I.,Wang, J.S. 한국항해항만학회 1987 한국항해학회지 Vol.11 No.2
It is well known that the height of tank metacenter above the centroid of fluid in a tank is given by i/v where I is the inertia moment of free surface and v is the fluid volume. It is supposed in this formula that the inclination of ship is small and that the free surface of fluid do not touch the top and the bottom of tank. It the inclination of ship is large, the height of tank metacenter may be possibly greater than that given by i/v. The height of tank metacenter is smaller than i/v when the free surface of fluid touch the top or the bottom of tank. The reasonable method to calculate the height of tank metacenter is presented in this paper and prepared in FORTRAN program by FUNCTION EFFRES. The approximate formula was also developed and given by $g_m=(1+\frac{2}{1}tan^2\theta)[1-EXP\{-12(\frac{\alpha(1-\alpha)k}{tan\theta})^{1.25}\}]\frac{i}{v}$ where $g_m$ is the distance from the centroid of fluid to the tank metacenter, $\theta$ is inclined angle of ship, $\alpha$ is the ratio of filled volume to tank capacity and k is the ratio of the depth to the width of tank. The values calculated by the approximate formula given in this paper were compared with the exact values from the computer program and proved out to be sufficiently precise for practical use.
-
軸心이 不一致한 船尾管 密封裝置에서 시일 링의 擧動과 應力解析에 關한 硏究
전효중(H.J.Jeon),왕지석(J.S. Wang),김영주(Y.J. Kim),남연길(J.K. Nam) 한국해양대학교 해사산업연구소 1991 海事産業硏究所論文集 Vol.1 No.-
To analize the behaviour of seal rings in the stern tube sealing system of which the propeller shaft is eccentric to the stern tube, stress analysis of axi-symetric body with non-symetric loading and non-symetric given displacements is investigated in this paper using the finite element method. As the non-symetric loads and non-symetric given displacements of axi-symetric body are generally periodic functions of angle e, the nodal forces and nodal displacements can be expanded in cosine and sine series, that is, Fourier series. Furthermore, using Euler's formula, the cosine and sine series can be converted into exponential series and it is proved that the related calculus become more clear. Substituting the nodal displacements expanded in Fourier series into the strain components of cylindrical coordinates system, the element strains are expressed in series form and by the principal of virtual work, the element stiffnes martix and element load vector are obtained for each order. It is also shown that if the non-symetric loads are even or odd functions of angle e, the stiffness matrix and load vector of the system are composed with only real numbers and relatively small capacity of computer memory is enough for caculation.
-
전효중(H.J. Jeon),왕지석(J.S. Wang),김의간(U.K. Kim),김수열(S.Y. Kim) 한국해양대학교 해사산업연구소 1991 海事産業硏究所論文集 Vol.1 No.-
Lip type stern tube sealing systems have used in almost all the middle or large ships which are being constructed in these days. It seems that the pressure fluctuation of the seal ring interspace, the cross-section profile and the materials quality of the seal rings have great effects on the sealing function of this sealing system. In this paper, the mechanical movement of lip seal ring which plays the most important role in stern tube sealing system and the possibility of leakage caused by pressure fluctuation are studied by theory and experiment. Using the finite element method for the axi-symetric object which receives the torsional load, the displacement and stress analysis of the seal rings are executed for products of several representaitive manufactrers of seal rings, and also the possibility of crack occurance is checked by theoretical analysis. If the force which seal ring lip periphery receives is too small, there will be the possibility of leakage caused by the pressure fluctuation of the seal ring interspace, and if this force is too large, the frictional force between the seal ring and the liner will become large, the excessve wear of lip tip will occurs, and in the end its endurance will become problematical. The possibility of leakage caused by hardening of seal ring materials and creep phenomena of tested seal rings are also examined. The trial seal rings were designed and manufactured using the porgram of displacement and stress analysis developed in this study and the experimantal apparatus to test the trial seal rings was also designed and manufactured. This trial seal rings were fitted in the experimental apparatus which was made in the same form as an actual stern tube. The one side of this apparatus was filled with sea water and the other side of it was filled with the lubricating oil. The leakage of oil and sea water was checked and the temperature was measured, rotating the propeller shaft at the constant velocity by D.C. motor. It was proved that the trial seal rings made in Viton rubber functioned excellenty but the trial seal rings made in N.B.R. rubber had problem in its durability.
-
-
부분구조합성법에 의한 동력전달 변환기의 진동해석에 관한 연구
박영철,박석주,왕지석 韓國海洋大學校 附設 海洋科學技術硏究所 1999 硏究論文集 Vol.8 No.-
As shipbuilding industry hans being developed so far the industrial structure in korea also has been making surprising upturn and reform. To keep up with the up-to-date technology of the advanced shipbuilding industry, continuous researches and study have priority over the investment and promotion which have relation to minimize noise, vibration, shape, and expense. In this paper I intend to minimize the weight of a converter with unchanged natural frequency about light weighted ship which supports the weight of propeller shaft and has enough stiffness vibration originated from the motion of the propeller shaft. The weight minimization is performed by the Sensitivities of the Natural frequencies of the converter. To decrease a power transmission converter weight ideally, the parts of the sensitivity zero are to be but mainly, and the changing quantity of natural frequency by the cut is to be recovered by the structural modification for the parts with the good sensitivity. But, as actually the mathematical solution for the homogeneous problem( i. e. 0 object function) do not exist, we hereby redesign a converter with much thinner thickness and recover the natural frequencies and natural modes to original structure's by the sensitivity analysis. And the Frequency Response Function(FRF) are to bo observed for the interesting points. In the analysis, the original thickness of a converter model has 84mm of thickness, and the thickness is 60mm and 70mm. And we are to try to recover the 1, 2, 4 lower natural frequencies interested.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
