Vibration Frequencies of Truncated-Cone and Wedge Beams

1965 ◽  
Vol 32 (4) ◽  
pp. 932-934 ◽  
Author(s):  
H. D. Conway ◽  
J. F. Dubil
Keyword(s):  
Cross Section ◽  
Numerical Results ◽  
Cantilever Beams ◽  
Vibration Frequencies ◽  
Resonant Frequencies ◽  
Simply Supported ◽  
Truncated Cone ◽  
End Conditions ◽  
Uniform Cross Section

In the first part of a recent paper,2 numerical results were presented for the first five transverse vibrational resonant frequencies of truncated-cone cantilever beams for a number of different geometrics. These results are now extended to include the nine possible combinations of the simply supported, clamped, and free end conditions. The corresponding numerical results for the vibrating truncated wedge are also presented. The foregoing data augment the numerical results for the first five frequencies of uniform cross-section beams given in the recent handbook by Harris and Crede.4

Vibration Frequencies of Tapered Bars and Circular Plates

1964 ◽  
Vol 31 (2) ◽  
pp. 329-331 ◽  
Author(s):  
H. D. Conway ◽  
E. C. H. Becker ◽  
J. F. Dubil
Keyword(s):  
Free Vibration ◽  
Test Cases ◽  
Cantilever Beams ◽  
Vibration Frequencies ◽  
Circular Plates ◽  
Approximate Methods ◽  
Resonant Frequencies ◽  
Simply Supported ◽  
Tapered Plates ◽  
Special Case

Calculations are made of the values of the transverse vibrationa resonant frequencies for truncated-cone cantilever beams for a number of geometries, the boundary conditions being clamped/free, clamped/simply supported, and clamped/clamped. After noting an analogy which exists between the free vibration of cones and linearly tapered plates for the special case when Poisson’s ratio = 1/3, data are also given for the resonant axisymmetrical frequencies of clamped tapered circular plates. Some data for partially tapered plates are also computed. Aside from their value for design purposes, these data can be used as test cases for assessing the accuracy of various approximate methods of solution.

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

1981 ◽  
Vol 48 (1) ◽  
pp. 169-173 ◽  
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.

Nonlinear resonant oscillations of a gas in a tube of varying cross-section

1994 ◽  
Vol 444 (1922) ◽  
pp. 591-604 ◽  
Keyword(s):  
Cross Section ◽  
The Other ◽  
Suitable Choice ◽  
Resonant Frequencies ◽  
Rigid Barrier ◽  
Uniform Cross Section

An investigation is made of the oscillations produced in a gas contained in a tube closed at one end by a rigid barrier and at the other by a piston vibrating at near resonant frequencies. For a tube of uniform cross-section this problem is now well documented. The purpose of this investigation is to demonstrate that a tube of varying cross-section can produce significant changes in the solution for quite small variations. In particular a complicated Duffing like response is possible, with solutions that are not unique for certain frequencies. A significant increase in amplitude occurs relative to non-resonant oscillations and relative to resonant oscillations in a tube of uniform cross-section. This increase can be further enhanced by suitable choice of the variations in cross-section.

Vibration and Damping Analysis of Curved Multilayered Beams

1985 ◽  
Vol 9 (2) ◽  
pp. 59-63
Author(s):  
J. Vaswani ◽  
N.T. Asnani ◽  
B.C. Nakra
Keyword(s):  
Equations Of Motion ◽  
Harmonic Excitation ◽  
Governing Equations ◽  
Resonant Frequencies ◽  
Constant Weight ◽  
Simply Supported ◽  
Constant Size ◽  
End Conditions ◽  
Multilayered Beam ◽  
Viscoelastic Layers

Governing equations of motion for a general curved multilayered beam with alternate elastic and viscoelastic layers, subjected to harmonic excitation are derived using an energy method. A solution for simply supported end conditions has been obtained, to determine the resonant frequencies and associated system loss factors of beams with 3, 5 and 7 layers. Both constant size and constant weight criteria have been used for comparison.

scholarly journals Identification of an open crack in a beam with variable profile by two resonant frequencies

2016 ◽  
Vol 24 (5) ◽  
pp. 839-859 ◽  
Author(s):  
Lourdes Rubio ◽  
José Fernández-Sáez ◽  
Antonino Morassi
Keyword(s):  
A Priori ◽  
Sufficient Conditions ◽  
Flexural Vibration ◽  
Open Crack ◽  
Frequency Data ◽  
Resonant Frequencies ◽  
Simply Supported ◽  
End Conditions ◽  
Theoretical Results ◽  
Elastic Spring

We consider the identification of a single open crack in a simply supported beam having nonuniform smooth profile and undergoing infinitesimal in-plane flexural vibration. The profile is assumed to be symmetric with respect to the mid-point of the beam axis. The crack is modeled by inserting a rotational linearly elastic spring at the damaged cross-section. We establish sufficient conditions for the unique identification of the crack by a suitable pair of natural frequency data, and we present a constructive algorithm for determining the damage parameters. The result is proved under a technical a priori assumption on the zeros of a suitable function determined in terms of the eigenfunctions of the problem. Extensions to beams under different sets of end conditions are also discussed. Theoretical results are confirmed by an extensive numerical investigation, both on simulated and experimental data.

scholarly journals A Multi-Mode Broadband Vibration Energy Harvester Composed of Symmetrically Distributed U-Shaped Cantilever Beams

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 203
Author(s):  
Xiaohua Huang ◽  
Cheng Zhang ◽  
Keren Dai
Keyword(s):  
Energy Harvester ◽  
Low Frequency ◽  
Experimental Results ◽  
Vibration Energy ◽  
Cantilever Beams ◽  
Resonant Frequencies ◽  
Promising Alternative ◽  
Piezoelectric Energy ◽  
Straight Beam ◽  
Resonance Frequencies

Using the piezoelectric effect to harvest energy from surrounding vibrations is a promising alternative solution for powering small electronic devices such as wireless sensors and portable devices. A conventional piezoelectric energy harvester (PEH) can only efficiently collect energy within a small range around the resonance frequency. To realize broadband vibration energy harvesting, the idea of multiple-degrees-of-freedom (DOF) PEH to realize multiple resonant frequencies within a certain range has been recently proposed and some preliminary research has validated its feasibility. Therefore, this paper proposed a multi-DOF wideband PEH based on the frequency interval shortening mechanism to realize five resonance frequencies close enough to each other. The PEH consists of five tip masses, two U-shaped cantilever beams and a straight beam, and tuning of the resonance frequencies is realized by specific parameter design. The electrical characteristics of the PEH are analyzed by simulation and experiment, validating that the PEH can effectively expand the operating bandwidth and collect vibration energy in the low frequency. Experimental results show that the PEH has five low-frequency resonant frequencies, which are 13, 15, 18, 21 and 24 Hz; under the action of 0.5 g acceleration, the maximum output power is 52.2, 49.4, 61.3, 39.2 and 32.1 μW, respectively. In view of the difference between the simulation and the experimental results, this paper conducted an error analysis and revealed that the material parameters and parasitic capacitance are important factors that affect the simulation results. Based on the analysis, the simulation is improved for better agreement with experiments.

Sign in / Sign up

Export Citation Format

Share Document