• Title/Summary/Keyword: Receptance

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Vibration Analysis of Frame Structural Systems by the Receptance Method (Receptance 방법에 의한 골조구조계의 진동해석)

  • S.Y. Han;K.C. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.2
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    • pp.174-186
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    • 1991
  • There exist many frame structural systems which may be regarded as a combined structural system composed of beam/bar elements and attachments reducible to damped spring-mass systems. In this paper, analytical methods based on the receptance for the vibration analysis of such a system are presented. For the free vibration analysis and response calculations to point excitations, receptances of a uniform Timoshenko beam and a bar are derived in closed and spectral forms, and the method to obtain the system receptance by synthesizing the receptances of the elements and other subsystems is presented. The system damping property is also obtainable by sysnthesizing the components' damping properties. For calculations of the system responses to support motion, the Support Displacement Transfer Ratio(SDTR) of a uniform Timoshenko beam and a bar conceptually similar to the receptance is defined, and the method of synthesizing them with other subsystems' receptances is also presented. Such a method is very convenient especially in dynamic reanalysis subject to changes of some design variables.

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Vibration Analysis of Mindlin-Plate Structures having Attachments by the Receptance Method (Receptance 방법에 의한 부가물을 갖는 Mindlin판유추 구조제의 진동해석)

  • S.Y. Han;J.H. Chung
    • Journal of the Society of Naval Architects of Korea
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    • v.32 no.3
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    • pp.98-106
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    • 1995
  • In ship and offshore structures, there exist many local structural systems which may be regarded as a combined structural systems composed of thick plates or double wall panels and attachments reducible to damped spring-mass systems. For vibration analysis of such a combined system an analytical method based on the receptance method is presented in this paper. The free vibrational characteristics and forced vibration responses of the combined system can be calculated by synthesis of receptances of the panel and attachments. To calculate receptances of the panel, it may be regarded as a Mindlin plate for consideration of effects of shear deformation and rotary inertia and the assumed mode-Lagrange's equation method is applied using Timoshenko beam function or polynomials having properties of Timoshenko beam function as trial functions. Through some numerical calculations, accuracy and efficiency of the presented method are shown.

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Structure-borne Noise Analysis of Marine Diesel Engine Considering Receptance of Hull Structure at Mounting Point (선체 마운트 지지점에서의 리셉턴스를 고려한 선박용 디젤 엔진의 고체전달음 해석)

  • Jang, Seong-Gil;Jeong, Weui-Bong;Hong, Chin-Suk;Bae, Soo-Ryong
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.2
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    • pp.120-128
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    • 2011
  • This paper presents an efficient method to analyze noise and vibration of marine diesel engines mounted on flexible hull structure. The analysis model should in general include the hull structure, leading to lots of computational efforts. To minimize the computational efforts, in this paper, the transfer synthesis utilizing the receptance at the mounting points is proposed. The procedure is then verified by comparing the results with those from the full model calculation. The effects of flexible hull structure on the acoustic power from engine block are finally investigated. It is found that the effect of the hull is significant when the receptance of hull structure is similar to or greater than that of mount or engine block.

A Free Vibration Analysis of the Continuous Circular Cylindrical Shell with the Multiple Simple Supports Using the Receptance Method (동적응답법을 이용한 다점 단순지지된 연속원통셸의 자유진동 해석)

  • 이영신;한창환
    • Journal of KSNVE
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    • v.10 no.6
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    • pp.998-1008
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    • 2000
  • The continuous circular cylindrical shells are widely used for the high performance structures of aircraft, spacecraft, missile, nuclear fuel rod shell etc.. In this paper, a method for the free vibration analysis of the continuous circular cylindrical shells with the multiple simple supports is developed by using the receptance method. With this method, the vibrational characteristics of the continuous system is analyzed by considering as a combined structure. The system receptance is also derided by the application of the equilibrium of forces and the continuity of displacements at the support points. The natural frequencies and mode shapes are calculated numerically and they are compared with the FEM results to improve the reliability of analytical solution. Numerical results on the 4-equal-span continuous circular cylindrical shell are presented in this paper.

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Free Vibration Analysis of Clamped-Free Circular Cylindrical Shells with Circular Plate at Top (원판 덮개를 갖는 고정-자유 원통셸의 고유진동 해석)

  • 임정식;이영신
    • Journal of KSNVE
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    • v.6 no.6
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    • pp.801-818
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    • 1996
  • Free vibration analyses of circular cylindrical shells attached with plate structures for the symmetric boundary condition such as simply-simply supported shells by receptance method are found in literatures. However analyses of those shells with unsymmetric boundary condition as clamped free boundary are hardly found. Here frequency equation of the clamped free circular cylindrical shell with end plate is derived using receptance method and natural frequencies of the combined system were calculated. The frequencies and mode shapes obtained from present method are compared with those of ANSYS to show the validity of the method. Natural frequencies and mode component ratios of clamped-free cylindrical shell are obtained by employing Rayleigh-Ritz method on energy equations, and they are used in receptance calculation. Results show good agreement with those of ANSYS analyses.

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The Study of Continuous System Combined with Distributed DVA (II) (분포질량 동흡진기가 부착된 연속체 시스템에 대한 연구 (II))

  • Choi, Jeung-Hyun;Lim, Byoung-Duk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.3
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    • pp.215-221
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    • 2004
  • Large machine and structure can not be normally treated as lumped parameter system. Such machine or structure must be broken down to individual beams or panels the motion of which must be analysed before an absorber system can be designed for each element. The absorber may be a lumped parameter system or a continuous system. One of the most common elements in a machine or structure is the cantilever, and in this paper is considered the design of a continuous parameter absorber to reduce the transverse vibrations of a beam. So this paper describes the method to obtain the accurate information about combined continuous beam system with DVA. This information is obtained from the combined system's receptance. and this paper shows the convenience and useful informations when design the dynamic vibration absorber with the combined system's receptance.

The Study of DVA used to Transfer Function (I) (전달함수를 이용한 동흡진기 설계에 대한 연구(I))

  • Choi, Joung-Hyun;Lim, Byoung-Duk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.9
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    • pp.1457-1462
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    • 2003
  • The problem of reducing the level of vibrations in structures arises in various branches of technology. For the calculation of systems equipped with DVAs, the frequencies of the protected system's free vibrations are determined first. In most practical problems system have to be considered continuous systems. It is important to obtain the detailed information about not the first frequency and the mode but anothers corresponding to it. So, this paper describes the method to obtain the accurate information about the combined discrete system. This information is obtained from the combined system's receptance. This paper shows the convenience when design the dynamic vibration absorber with the combined system's receptance.

Free Vibration Analysis of a Circular Cylindrical Shell with a Spherical Cap (구형 캡이 결합된 외팔 원통 쉘의 고유진동 해석)

  • J.S. Yim;D.S. Sohn
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11a
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    • pp.355.2-355
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    • 2002
  • The receptance method was applied for the analysis of a cylindrical shell with a spherical cap attached at an arbitrary axial position of the shell. The boundary condition of the shell considered here was clamped-free condition. Before the analysis of the shell/spherical cap combined structure, natural frequencies of the cap and the shell were calculated separately and then they were used in the calculation of the frequencies of the combined structure by the receptance method. (omitted)

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Prediction of vibration and noise from steel/composite bridges based on receptance and statistical energy analysis

  • Liu, Quanmin;Liu, Linya;Chen, Huapeng;Zhou, Yunlai;Lei, Xiaoyan
    • Steel and Composite Structures
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    • v.37 no.3
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    • pp.291-306
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    • 2020
  • The noise from the elevated lines of rail transit has become a growing problem. This paper presents a new method for the rapid prediction of the structure-borne noise from steel or composite bridges, based on the receptance and Statistical Energy Analysis (SEA), which is essential to the study of the generation mechanism and the design of a low-noise bridge. First, the vertical track-bridge coupled vibration equations in the frequency domain are constructed by simplifying the rail and the bridge as an infinite Timoshenko beam and a finite Euler-Bernoulli beam respectively. Second, all wheel/rail forces acting upon the track are computed by taking a moving wheel-rail roughness spectrum as the excitation to the train-track-bridge system. The displacements of rail and bridge are obtained by substituting wheel/rail forces into the track-bridge coupled vibration equations, and all spring forces on the bridge are calculated by multiplying the stiffness by the deformation of each spring. Then, the input power to the bridge in the SEA model is derived from spring forces and the bridge receptance. The vibration response of the bridge is derived from the solution to the power balance equations of the bridge, and then the structure-borne noise from the bridge is obtained. Finally, a tri-span continuous steel-concrete composite bridge is taken as a numerical example, and the theoretical calculations in terms of the vibration and noise induced by a passing train agree well with the field measurements, verifying the method. The influence of various factors on wheel/rail and spring forces is investigated to simplify the train-track-bridge interaction calculation for predicting the vibration and noise from steel or composite bridges.

Free Vibration Analysis of a Curvatured Plate Welded to a Clamped-Free Circular Cylindrical Shell (곡률 원판이 결합된 외팔 원통 쉘의 고유진동 해석)

  • Yim, J.S.;Sohn, D.S.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2002.11b
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    • pp.529-534
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    • 2002
  • The receptance method was applied for the analysis of a cylindrical shell with a curvaturated plate attached at the top of the shell. The boundary conditions of the shell considered here were clamped at the bottom and free at the top of the shell. Before the analysis of the shell/plate combined structure, the natural frequencies of the plate and the shell were calculated separately and then they were used in the calculation of the frequencies of the combined structure by the receptance method. The frequency equation of the combined structure was derived from the continuity condition at the junction of the shell and the plate. The frequencies for various curvature factors of the plate were presented and compared with those from ANSYS to show its validity of the present method.

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