Transverse Vibration Characteristics of an Inclined Cantilevered Rectangular Prism in flow direction

Free-vibration tests of a cantilevered rectangular prism with a side ratio of less than D/H = 0.5 (D, depth of the rectangular prism in the flow direction; H, height of a rectangular prism) that experiences low-speed galloping at a lower reduced velocity than the resonant reduced velocity were conducted in a water tunnel. We also carried out a power generation experiment using an iron-gallium alloy, which is a magnetostrictive material, to investigate the possibility of harvesting energy from a flow-induced transverse vibration. The effects of the side ratio of the rectangular prism and the configuration of a fin that was fitted on the back of a rectangular prism to increase the flexural rigidity on the response amplitude were investigated. The vibration of a rectangular prism with D/H = 0.1 occurred at a lower reduced velocity than that of the other rectangular prisms. This prism has the largest increment rate of the non-dimensional response amplitude ηrms for reduced velocity Vr, and the vibration has an uniform amplitude for each reduced velocity. The reduced velocity at the 20% non-dimensional response amplitude of a rectangular prism Vr0.2 decreases linearly with decreasing side ratio D/H. The response amplitude of the rectangular prism with D/H = 0.2 is only slightly dampened for all values of the reduced mass-damping parameter Cn. The values of Vr0.2 of the rectangular prism with a fin increased as the depth ratio of the fin increased. The response amplitude of the rectangular prism with/without a fin was found to be related to the second moment of area of the prism. The energy harvester using magnetostrictive material and a rectangular prism with D/H = 0.2 generates a maximum electric power of 8.8 mW.

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Sheet Material Property Effects upon Dynamic Behavior in Self-Pierce Riveted Joints

Materials Science Forum ◽

10.4028/www.scientific.net/msf.675-677.999 ◽

2011 ◽

Vol 675-677 ◽

pp. 999-1002 ◽

Cited By ~ 2

Author(s):

Xiao Cong He

Keyword(s):

Natural Frequency ◽

Transverse Vibration ◽

Spot Welding ◽

Sheet Material ◽

Vibration Characteristics ◽

Efficient Design ◽

Material Density ◽

Sheet Materials ◽

Riveted Joints ◽

Free Transverse Vibration

Self-pierce riveting (SPR) technology offers an alternative to resistance spot welding (RSW) for joining sheet materials. It has been found that the SPR technology produced a much stronger joint than the RSW in fatigue test. For efficient design of SPR structures, the knowledge of dynamic characteristics of the SPR beams is essential. In this paper, the free transverse vibration characteristics of single lap-jointed cantilevered SPR beams are investigated in detail. The focus of the analysis is to reveal the influence on the natural frequency and natural frequency ratio of these beams caused by variations in the material properties of sheet materials to be jointed. It is shown that the transverse natural frequencies of single lap jointed cantilevered SPR beams increase significantly as the Young’s modulus of the sheet materials increases, but change slightly corresponding to the change in Poisson’s ratio. It is also found that the material density of the sheets have significant effects on the free transverse vibration characteristics of the beams.

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Free Vibration of Thin-Walled Open Section Beams With Unconstrained Damping Treatment

Journal of Applied Mechanics ◽

10.1115/1.3157561 ◽

1981 ◽

Vol 48 (1) ◽

pp. 169-173 ◽

Cited By ~ 7

Author(s):

S. Narayanan ◽

J. P. Verma ◽

A. K. Mallik

Keyword(s):

Free Vibration ◽

Cross Section ◽

Transverse Vibration ◽

Natural Frequencies ◽

Vibration Characteristics ◽

Numerical Results ◽

Simply Supported ◽

Clamped Beams ◽

Thin Walled ◽

Open Cross Section

Free-vibration characteristics of a thin-walled, open cross-section beam, with unconstrained damping layers at the flanges, are investigated. Both uncoupled transverse vibration and the coupled bending-torsion oscillations, of a beam of a top-hat section, are considered. Numerical results are presented for natural frequencies and modal loss factors of simply supported and clamped-clamped beams.

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Vibration Characteristics for Moving Printing Membrane with Variable Density along the Lateral Direction

Shock and Vibration ◽

10.1155/2017/2968705 ◽

2017 ◽

Vol 2017 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Mingyue Shao ◽

Jimei Wu ◽

Yan Wang ◽

Qiumin Wu ◽

Yuan Chen

Keyword(s):

Density Distribution ◽

Transverse Vibration ◽

High Speed ◽

Differential Quadrature Method ◽

Variable Density ◽

Vibration Characteristics ◽

Lateral Direction ◽

Vibration Model ◽

The Stability ◽

Density Coefficient

The vibration model of moving membrane with variable density distribution is established, and the density distribution of the moving membrane varies along the lateral direction. The transverse vibration differential equations of moving membrane are established based on D’Alembert’s principle and discretized by using the differential quadrature method (DQM). The relationships of the first three dimensionless complex frequencies between dimensionless speed, density coefficient, and tension ratio of the membrane are analyzed by numerical calculation. The effects of the density coefficient and the tension ratio on transverse vibration characteristics of the membrane are investigated. The relationship between density coefficient and critical speed is obtained. The numerical results show that the density coefficient and the tension ratio have important influence on the stability of moving membrane. So the study provides a theoretical basis for improving the working stability of the membrane in the high-speed printing process.

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Experimental measurements on transverse vibration characteristics of piezoceramic rectangular plates by optical methods

Journal of Sound and Vibration ◽

10.1016/j.jsv.2004.10.010 ◽

2005 ◽

Vol 286 (3) ◽

pp. 587-600 ◽

Cited By ~ 13

Author(s):

Chien-Ching Ma ◽

Hsien-Yang Lin

Keyword(s):

Transverse Vibration ◽

Vibration Characteristics ◽

Optical Methods ◽

Experimental Measurements ◽

Rectangular Plates

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Research on Vibration Characteristics of Barrel Considered Gas Pressure

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.727-728.501 ◽

2015 ◽

Vol 727-728 ◽

pp. 501-504 ◽

Cited By ~ 1

Author(s):

Da Wei Zhu ◽

Jie Zhou ◽

Xue Ping Zhang

Keyword(s):

Transverse Vibration ◽

Great Influence ◽

Forced Response ◽

Vibration Characteristics ◽

Gas Pressure ◽

Charge Weight ◽

Considerable Influence ◽

Analysis Method ◽

Vibration Equation ◽

Simulation Results

The vibration of barrel has considerable influence on accuracy when firing, for obtaining the disciplinarian of barrel vibration, barrel is considered as a cantilever in this paper, on that base, its transverse vibration equation has been established, and forced response can be figured out by using modal analysis method. The vibration characteristics of barrel were numerically simulated for different charge weight, besides, two situations that the barrel with or without gas pressure have been compared. In solving process, the displacement、velocity and acceleration of projectile are real dates. The simulation results indicate that static offset has a great influence on vibration characteristics, with the increasing of the projectile′s initializing speed, the amplitude of the barrel′s vibration is lower without static offset, and the effect of gas pressure can decrease the amplitude of vibration considerably.

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