• Title/Summary/Keyword: Newmark

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Theoretical Analysis on Transient Torsional Vibrations of Two Stroke Low Speed Diesel Engines

  • Lee, Don-Chool;Kim, Sang-Hwan;Yu, Jung-Dae
    • Journal of Advanced Marine Engineering and Technology
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    • v.31 no.3
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    • pp.207-214
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    • 2007
  • Theoretical analysis on transient torsional vibration was started from the early 1960s for high power synchronous motor application. Particularly. its simulation and measuring techniques in marine diesel engine field have been steadily studied by some classification societies and large marine diesel engine designers. This paper introduces the simulation method on transient torsional vibration of two stroke low speed diesel engine using the Newmark method.

The Comparision of Analysis Methods in dynamic Design of Dam based on Shaking Table tests (진동대시험에 근거한 댐의 내진설계시 해석 방법의 비교)

  • Hwang, Seong-Choon;Oh, Byung-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.732-737
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    • 2005
  • This paper performed pseudo static analysis and dynamic analysis for CFRD and evaluated reliability with the results of Shaking Table Test. The Seismic coefficient method, modified seismic coefficient method, Newmark method of Pseudo static analysis and frequency domain response analysis, time domain history analysis of dynamic analysis were used. The analysis results were differ between analysis method, but the trends of acceleration and displacement were good agreement with the results of shaking table test.

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Analysis of the 3-D Stress Wave in a Plate under Impact Load by Finite Element Method

  • Jin, Sung-Hoon;Hwang, Gab-Woon;Cho, Kyu-Zong
    • International Journal of Precision Engineering and Manufacturing
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    • v.2 no.2
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    • pp.5-10
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    • 2001
  • This paper attempt to explore the shape of stress wave propagation of 3-dimensional stress field which in made in the process of the time increment. A finite element program about 3-dimensional stress wave propagation is developed for investigating the changing shape of the stress by the impact load. The finite element program, which is the solution for the 3-dimensional stress wave analysis, based on Galerkin and Newmark-${\beta}$ method at time increment step. The tensile stress and compressive stress become larger with the order of the middle , the upper and the opposite layers when the impact load is applied. In a while the shear stress become larger according to the order of the upper, the middle and the opposite layers when impact load applied.

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Geometric Nonlinear Analysis of Flexible Media Using Dynamic FEM (동적유한요소법을 이용한 유연매체의 기하비선형해석)

  • Jee, Jung-Geun;Hong, Sung-Kwon;Jang, Yong-Hoon;Park, No-Cheol;Park, Young-Pil
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2006.11a
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    • pp.721-724
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    • 2006
  • In the development of sheet-handling machinery, it is important to predict the static and dynamic behavior of the sheets with a high degree of reliability. Flexible media is very thin, very light and very flexible so it behaves geometric nonlinearity of large displacement and large rotation but small strain. In this paper, static and dynamic analyses of flexible media are performed by dynamic FEM considering geometric nonlinearity. Mass and tangent stiffness matrices based on the Co-rotational(CR) approach are derived and numerical simulations are performed by full Newton-Raphson(FNR) method and Newmark integration scheme.

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A study on the Transient Torsional Vibrations of Four Stroke Marine Diesel Engines (선박용 4행정 디젤엔진의 과도 비틀림 진동에 관할 연구)

  • Lee, D.C.;Yu, J.D.;Jeon, H.J.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.44-50
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    • 2002
  • Theoretical analysis on the transient torsional vibration was started from early 1960's for high power synchronous motor application. As for marine engineering, simulation and measuring techniques of transient torsional vibration have been steadily studied by manufacturer of flexible coupling and designer of four stroke marine diesel engine. In this paper, the simulation method of transient torsional vibration for four stroke marine diesel engine application using Newmark method is introduced.

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Seismic response of concrete columns with nanofiber reinforced polymer layer

  • Motezaker, Mohsen;Kolahchi, Reza
    • Computers and Concrete
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    • v.20 no.3
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    • pp.361-368
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    • 2017
  • Seismic response of the concrete column covered by nanofiber reinforced polymer (NFRP) layer is investigated. The concrete column is studied in this paper. The column is modeled using sinusoidal shear deformation beam theory (SSDT). Mori-Tanaka model is used for obtaining the effective material properties of the NFRP layer considering agglomeration effects. Using the nonlinear strain-displacement relations, stress-strain relations and Hamilton's principle, the motion equations are derived. Harmonic differential quadrature method (HDQM) along with Newmark method is utilized to obtain the dynamic response of the structure. The effects of different parameters such as NFRP layer, geometrical parameters of column, volume fraction and agglomeration of nanofibers and boundary conditions on the dynamic response of the structure are shown. The results indicated that applied NFRP layer decreases the maximum dynamic displacement of the structure. In addition, using nanofibersas reinforcement leads a reduction in the maximum dynamic displacement of the structure.

Hydroelastic Responses of a Very Large Floating Structure in Time Domain (시간영역에서 초대형 부유식 해양구조물에 대한 유탄성 운동해석)

  • 이호영;신현경
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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    • 2000.04a
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    • pp.18-22
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    • 2000
  • This paper is transient motions of a very large floating structure subjected to dynamic load induced by wave. A time domain method is applied to the hydroelasticity problems for this purpose. The method is based on source-dipole and FEM scheme and on Newmark $\beta$ method to pursuit time step process taking advantage of the memory effect. The present method is appied to hydroelastic response analysis in regular waves and impact responses due to dropping aircraft.

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The Safety Assessment of the Connecting Cable in Deep Water Unmanned Underwater Vehicle (심해 잠수정 연결케이블의 안전성 평가에 관한 연구)

  • Nho, In-Sik;Choi, Byoung-Gy;Lee, Jong-Moo
    • Journal of Ocean Engineering and Technology
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    • v.20 no.6 s.73
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    • pp.75-81
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    • 2006
  • In this study, the dynamic response of the umbilical cable in a deep-water unmanned underwater vehicle system was analyzed. In order to analyze the forces acting on the cable, the launcher and umbilical cable were modeled by the simple 1-D mass-spring system. Damping and dynamic analysis was carried out by a direct time integration scheme using the $Newmark-{\beta}$ method with inverse iteration procedure, considering the nonlinear drag forces acting on the launcher. The obtained results of the present study can be used for the design of connecting the structure of the launcher and cable of the UUV system.

Vibration Analysis of a Flexible Structure in a Motion (유연 구조물의 운동중 발생하는 진동의 해석)

  • 이신영
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.18 no.6
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    • pp.1503-1509
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    • 1994
  • An analysis method is suggested and experimentally studied in order to solve a vibration problem of a flexible structure while it is moving. In this method, substructure synthesis method, modal analysis method and Newmark's integral method were used. Total deformation of a structure was composed of quasistatic component and dynamic component. Rigid body modes were considered in calculation of dynamic component. Combining those two component, deformation behavior and a real structural model of a transfer feeder showed good agreements with computational results.

Dynamic Nonlinear Analysis of Stiffened Shell Structures (보강된 쉘구조의 동적 비선형해석)

  • 최명수;김문영;장승필
    • Journal of the Earthquake Engineering Society of Korea
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    • v.5 no.3
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    • pp.57-64
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    • 2001
  • For the dynamic nonlinear analysis of stiffened plate and shell structures, total Lagrangian formulation is presented based upon the degenerated shell element considering finite rotation effects. Assumed strain concept is adopted in order to overcome shear locking phenomena and to eliminate spurious zero energy mode. In the elasto-plastic analysis, the return mapping algorithm based on the consistent elasto-plastic tangent modulus is applied to collapse analysis of shell structures. Newmark integration method is used for dynamic nonlinear analysis of shell structures under dynamic forces.

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