• 한국소음진동공학회논문집
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• 제17권12호
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• pp.1201-1207
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• 2007

The Timoshenko beam theories are used to model the rotating shaft. The nondimensional equations of motion for the rotating shaft subjected to moving mass and compressive axial forces are derived by using Hamilton's principle. Influence of system parameters such as the speed ratio. the mass ratio and the Rayleigh coefficient is discussed on the response of the moving system. The effects of compressive axial forces are also included in the analysis. The results are presented and compared with the available solutions of a rotating shaft subject to a moving mass and a moving load.

• 대한기계학회논문집A
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• 제27권11호
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• pp.1815-1823
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• 2003

The vibrational system of this study consists of a cantilever pipe conveying fluid, the moving masses upon it and having an attached tip mass. The equation of motion is derived by using Lagrange's equation. The influences of the velocity and the inertia force of the moving mass and the velocities of fluid flow in the pipe have been studied on the dynamic behavior and the natural frequency of a cantilever pipe by numerical method. The deflection of the cantilever pipe conveying fluid is increased due to the tip mass and rotary Inertia. After the moving mass passed upon the cantilever pipe, the amplitude of pipe is influenced by energy variation when the moving mass fall from the cantilever pipe. As the moving mass increase, the frequency of the cantilever pipe conveying fluid is increased. The rotary inertia of the tip mass influences much on the higher frequencies and vibration mode.

• Steel and Composite Structures
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• 제35권1호
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• pp.61-76
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• 2020

In this paper, the dynamic behaviour of an inclined functionally graded material (FGM) beam with different boundary conditions under a moving mass is investigated based on the first-order shear deformation theory (FSDT). The material properties vary continuously along the beam thickness based on the power-law distribution. The system of motion equations is derived by using Hamilton's principle. The finite element method (FEM) is adopted to develop a general solution procedure. The moving mass is considered on the top surface of the beam instead of supposing it on the mid-plane. In order to consider the Coriolis, centrifugal accelerations and the friction force, the contact force method is used. Moreover, the effects of boundary conditions, the moving mass velocity and various material distributions are studied. For verification of the present results, a comparative fundamental frequency analysis of an FGM beam is conducted and the dynamic transverse displacements of the homogeneous and FGM beams traversed by a moving mass are compared with those in the existing literature. There is a good accord in all compared cases. In this study for the first time in dynamic analysis of the inclined FGM beams, the Coriolis and centrifugal accelerations of the moving mass are taken into account, and it is observed that these accelerations can be ignored for the low-speeds of the moving mass. The new provided results for dynamics of the inclined FGM beams traversed by a moving mass can be significant for the scientific and engineering community in the area of FGM structures.

• International Journal of Precision Engineering and Manufacturing
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• 제9권3호
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• pp.33-39
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• 2008

The effects of a double crack and tip masses on the dynamic behavior of cantilever beams with a moving mass are studied using numerical methods. The cantilever beams are modeled by applying Euler-Bernoulli beam theory. The cracked sections are represented by a local flexibility matrix connecting three undamaged beam segments. The influences of the crack, moving mass, and tip mass, and the coupling of these factors on the vibration mode and the frequencies of the double-cracked cantilever beams are determined analytically. The methodology provides a basis for analyzing the dynamic behavior of a beam with an arbitrary number of cracks and a moving mass.

• 한국소음진동공학회논문집
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• 제15권5호
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• pp.586-594
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• 2005

In this paper, we studied about the effects of the rotating cantilever pipe conveying fluid with a moving mass. The influences of a rotating angular velocity, the velocity of fluid flow and moving mass on the dynamic behavior of a cantilever pipe have been studied by the numerical method. The equation of motion is derived by using the Lagrange's equation. The cantilever pipe is modeled by the Euler-Bernoulli beam theory. When the velocity of a moving mass is constant, the lateral tip-displacement of a cantilever pipe is proportional to the moving mass and the angular velocity. In the steady state, the lateral tip-displacement of a cantilever pipe is more sensitive to the velocity of fluid than the angular velocity, and the axial deflection of a cantilever pipe is more sensitive to the effect of a angular velocity. Totally, as the moving mass is increased, the frequency of a cantilever pipe is decreased in steady state.

• 한국소음진동공학회논문집
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• 제12권11호
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• pp.840-846
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• 2002

The vibrational system of this study is consisted of a cantilever pipe conveying fluid, the moving masses upon it and an attached tip mass. The equation of motion is derived by using Lagrange equation. The influences of the velocity and the number of moving masses and the velocities of fluid flow in the pipe have been studied on the natural frequency of a cantilever pipe by numerical method. As the size and number of a moving mass increases, the natural frequency of cantilever pipe conveying fluid is decreased. When the first a moving mass Is located at the end of cantilever pipe, the increasing of the distance of moving masses make the natural frequency increase at first and third mode, but the frequency of second mode is decreased. The variation of natural frequency of the system is decreased due to increase of the number of a moving mass. The number and distance of moving masses effect more on the frequency of higher mode of vibration.

• 한국산학기술학회논문지
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• 제9권4호
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• pp.859-864
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• 2008

티모센포 회전축을 따라 이동하는 이동질량과의 동적상호작용에 관한 연구가 수행되었다. 이동질량의 속력이 티모센코축의 회전속도와 연계된 구속조건식을 도출하였다. 티모센코의 보 이론를 활용하여 시스템의 무차원방정식이 유도되었다. 이동질량의 속력을 포함하는 티모센코 축의 회전속도, 레일리히 계수, 축방향 압축력 등 다양한 무차원 변수들의 영향에 따른 회전축의 처짐과 주파수응답에 대한 해석이 수행되어졌다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.713-716
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• 2004

In this paper a dynamic behavior of a double-cracked cnatilver beam with a tip mass and the moving mass is presented. Based on the Euler-Bernoulli beam theory, the equation of motion is derived by using Lagrange's equation. The influences of the moving mass, a tip mass and double cracks have been studied on the dynamic behavior of a cantilever beam system by numerical method. The cracks section are represented by the local flexibility matrix connecting two undamaged beam segments. ,Therefore, the cracks are modelled as a rotational spring. Totally, as a tip mass is increased, the natural frequency of cantilever beam is decreased. The position of the crack is located in front of the cantilever beam, the frequencies of a double-cracked cantilever beam presents minimum frequency.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 추계학술대회논문초록집
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• pp.315.2-315
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• 2002

The vibrational system of this study consists of a cantilever pipe conveying fluid, the moving mass upon it and an attached tip mass. The equation of motion is derived by using Lagrange equation. The influences of the velocity of moving mass and the uniformly distributed tangential follower force have been studied on the dynamic behavior of a cantilever pipe by numerical method. While the moving mass moves upon the cantilever pipe, the velocity of fluid flow increase, the tip displacement of cantilever pipe conveying fluid is decreased. (omitted)

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.275-280
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• 2003

This paper discusses on the dynamic responsed of an elastically restrained beam under a moving mass of constant velocity. Governing equations of motion taking into account of all inertia effects of the moving mass were derived by Galerkin's mode summation method, and Runge-Kutta integration method was applied to solve the differential equations. Numerical solutions for dynamic deflections of beams were obtained for the changes of the various parameters (spring stiffness, spring position, mass ratios and velocity ratios of the moving mass). In order to verify the numerical predictions for the dynamic response of the beam, experiments were conducted. Numerical solutions for the dynamic responses of the test beam have a good agreement with experimental ones.