• 제목/요약/키워드: Transfer Matrix

검색결과 876건 처리시간 0.024초

전달행렬법을 사용한 크랭크축의 3차원 진동해석 (The Transfer Matrix Method for Three-Dimensional Vibration Analysis of Crank Shaft)

  • 이정윤;오재응
    • 한국자동차공학회논문집
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    • 제5권4호
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    • pp.152-159
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    • 1997
  • This paper presents a vibration analysis method of crank shaft of six cylinder internal combustion engine. For simple analysis journal, pin and arm parts were assumed to have uniform section. Transfer Matrix Method was used, considering branched part and coordinate transformation part. Natural frequencies, modeshapes and transfer functions of crank shaft were investigated based upon the Euler beam theory: It was shown that the calculated natural frequencies, modeshapes agree well with the existing paper results.

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Natural frequencies and mode shapes of thin-walled members with shell type cross section

  • Ohga, M.;Shigematsu, T.;Hara, T.
    • Steel and Composite Structures
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    • 제2권3호
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    • pp.223-236
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    • 2002
  • An analytical procedure based on the transfer matrix method to estimate not only the natural frequencies but also vibration mode shapes of the thin-walled members composed of interconnected cylindrical shell panels is presented. The transfer matrix is derived from the differential equations for the cylindrical shell panels. The point matrix relating the state vectors between consecutive shell panels are used to allow the transfer procedures over the cross section of the members. As a result, the interactions between the shell panels of the cross sections of the members can be considered. Although the transfer matrix method is naturally a solution procedure for the one-dimensional problems, this method is well applied to thin-walled members by introducing the trigonometric series into the governing equations of the problem. The natural frequencies and vibration mode shapes of the thin-walled members composed of number of interconnected cylindrical shell panels are observed in this analysis. In addition, the effects of the number of shell panels on the natural frequencies and vibration mode shapes are also examined.

전달행렬법에 의한 반구 원통형 쉘구조의 해석 (An Analysis of Hemisphere-cylindrical Shell Structure by Transfer Matrix Method)

  • 김용희;이윤영
    • 한국농공학회지
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    • 제45권4호
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    • pp.115-125
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    • 2003
  • Shell structures are widely used in a variety of engineering application, and mathematical solution of shell structures are available only for a few special cases. The solution of shell structure is more complicated when it has such condition as winkler foundation, other problems. In this study many simplified methods (analogy of beam on elastic foudation, finite element method and transfer matrix method) are applied to analyze a hemisphere-cylindrical shell structures on elastic foundation. And the transfer matrix method is extensively used for the structural analysis because of its merit in the theoretical backgroud and applicability. Therefore, this paper presents the analysis of hemisphere-cylindrical shell structure base on the transfer matrix method. The technique is attractive for implementation on a numerical solution by means of a computer program coded in FORTRAN language with a few elements. To demonstrate this fact, it gives good results which compare well with finite element method.

회전축요소의 전달행렬의 이용과 진동해석 (Using of Transfer Matrix for Shaft Element and Vibration Analysis)

  • 전오성
    • 한국소음진동공학회논문집
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    • 제12권2호
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    • pp.161-169
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    • 2002
  • Based on the analytic expression for the elasto-dynamic behavior of rotating shaft, the transfer matrix is formulated for the shaft element with uniform cross-section. Timoshenko beam theory is Introduced for modeling the behavior of shaft. Complex variables representing the displacement, slope, moment and shear force are used for deriving the transfer matrix between both ends of the shaft element. Simulation result obtained by applying the transfer matrix to a general rotor model is compared with the reference result and proved to be exact. Natural frequencies and the corresponding modes are analyzed with varying the bearing: stiffness. The generally used bearings are considered for discussions. and the bearing stiffness is shown to affect the vibration characteristics of rotor.

전달행렬법에 의한 다중 다공판 흡음시스템의 흡음계수 예측 (Prediction of the Sound Absorption Coefficient for Multiple Perforated-Plate Sound Absorbing System by Transfer Matrix Method)

  • 허성춘;이동훈;권영필
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
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    • pp.653-658
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    • 2001
  • In this study, a new practical method of predicting the sound absorption coefficient for multiple perforated-plate sound absorbing system was developed using transfer matrix method. In order to validate the proposed method, the absorption coefficients calculated by transfer matrix method for single perforated plate were first compared with the absorption coefficients measured by SWR method according to different porosity, hole diameter, and thickness of the perforated plate. Based on the comparison results, transfer matrix method was further applied to double and triple perforated plates to evaluate the absorption coefficients. The experimental results showed that the absorption coefficients from transfer matrix method generally agreed well with the corresponding absorption coefficients from SWR method. However, due to the limitations of the impedance model used in this study, the measured values were differed with the calculated values for small porosity, hole diameter, and thickness in size of the perforated plate indicating the need of impedance model development for multiple perforated-plate sound absorbing system covering wide ranges of porosity, hole diameter, and thickness of the perforated plate.

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Free vibration analysis of asymmetric shear wall-frame buildings using modified finite element-transfer matrix method

  • Bozdogan, Kanat B.
    • Structural Engineering and Mechanics
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    • 제46권1호
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    • pp.1-17
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    • 2013
  • In this study, the modified finite element- transfer matrix methods are proposed for free vibration analysis of asymmetric structures, the bearing system of which consists of shear wall-frames. In the study, a multi-storey structure is divided into as many elements as the number of storeys and storey masses are influenced as separated at alignments of storeys. The shear walls and frames are assumed to be flexural and shear cantilever beam structures. The storey stiffness matrix is obtained by formulating the governing equation at the center of mass for the shear walls and the frames in the i.th floor. The system transfer matrix is constructed in the dimension of $6{\times}6$ by transforming the obtained stiffness matrix. Thus, the dimension, which is $12n{\times}12n$ in classical finite elements, is reduced to the dimension of $6{\times}6$. To study the suitability of the method, the results are assessed by solving two examples taken from the literature.

전달행렬법을 사용하여 균열이 있는 티모센코 보의 동특성 해석 (Dynamic Analysis of Cracked Timoshenko Beams Using the Transfer Matrix Method)

  • 김정호;곽종훈;이정우;이정윤
    • 한국소음진동공학회논문집
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    • 제26권2호
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    • pp.179-186
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    • 2016
  • This paper presents a numerical method that can evaluate the effect of crack for the in-plane bending vibration of Timoshenko beam. The method is a transfer matrix method that the element transfer matrix is deduced from the element dynamic stiffness matrix. An edge crack is expressed as a rotational spring, and then is formulated as an independent transfer matrix. To demonstrate the accuracy of this theory, the results computed from the present are compared with those obtained from the commercial finite element analysis program. Based on these comparison results, a parametric study is performed to analyze the effects for the size and locations of crack.

Vibration analysis of asymmetric shear wall and thin walled open section structures using transfer matrix method

  • Bozdogan, Kanat Burak;Ozturk, Duygu
    • Structural Engineering and Mechanics
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    • 제33권1호
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    • pp.95-107
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    • 2009
  • A method for vibration analysis of asymmetric shear wall and Thin walled open section structures is presented in this paper. The whole structure is idealized as an equivalent bending-warping torsion beam in this method. The governing differential equations of equivalent bending-warping torsion beam are formulated using continuum approach and posed in the form of simple storey transfer matrix. By using the storey transfer matrices and point transfer matrices which consider the inertial forces, system transfer matrix is obtained. Natural frequencies can be calculated by applying the boundary conditions. The structural properties of building may change in the proposed method. A numerical example has been solved at the end of study by a program written in MATLAB to verify the presented method. The results of this example display the agreement between the proposed method and the other valid method given in literature.

영향계수의 전달에 의한 환원판이 결합된 원추형 셸의 진동해석 (Vibration Analysis of Conical Shells with Annular Plates Using Transfer of Influence Coefficient)

  • 최명수;여동준
    • 동력기계공학회지
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    • 제19권5호
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    • pp.52-59
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    • 2015
  • This paper is presented for the free vibration of a conical shell with annular plates or circular plate using the transfer of influence coefficient. The governing equations of vibration of a conical shell, including annular plate, are written as a coupled set of first order differential equations by using the transfer matrix of the shell. Once the transfer matrix of a single component has been determined, the entire structure matrix is obtained by the product of each component matrix and the joining matrix. The natural frequencies and the modes of vibration were calculated numerically for joined conical-annular plates. The validity of the present method is demonstrated through simple numerical examples, and through comparison with the results of finite element method, transfer matrix method and ANSYS. The conclusion show that the present method can accurately obtain natural vibration characteristics of the conical shell with annular or circle end plates.

Transfer Matrix를 사용하여 예측한 $TiO_2$/Ag/$TiO_2$ 박막의 광학적 성질 및 스퍼터 증착된 박막과의 특성 비교 (Prediction of the optical properties of $TiO_2$/Ag/$TiO_2$ films using transfer matrix and comparisions with real transmittance measured on the sputter-deposited films)

  • 김진일;김진현;김영환;오태성
    • 한국재료학회지
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    • 제5권1호
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    • pp.140-148
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    • 1995
  • Transfer matrix를 사용하여 $TiO_{2}$ 및 Ag 단일 박막과 $TiO_{2}/Ag/TiO_{2}$ 다층 박막의 두계에 따른 투과도 특성을 예측하였으며, 이를 실제 스퍼터 증착하여 제조한 박막의 광학 특성과 비교하였다. $TiO_{2}$ 및 Ag 박막에서는 복소굴절률을 사용하므로써 실제 증착박막에서 측정된 특성과 근접한 투과도 곡선의 예측이 가능하였다. $TiO_{2}/Ag/TiO_{2}$ 3층 박막의 광학 특성은 Ag의 $TiO_{2}$층으로의 확산 및 응집에 의해 transfer matrix로 예측한 투과도 특성과 전혀 다른 거동을 나타내었다. 그러나 4nm 및 6nm 두계의 Ti 박막을 확산방지층으로 증착한 Ti$O_{2}$/Ti/Ag/Ti/Ti$O_{2}$ 구조의 5층 박막에서는 transfer matrix를 사용하여 예측한 $TiO_{2}/Ag/TiO_{2}$ 3층 박막의 투과도 곡선과 유사한 광학 특성을 얻을 수 있었다.

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