Theoretical and Experimental Study of Wave Propagation in Stressed Plate (original) (raw)
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Journal of the Acoustical Society of America, 2017
High order Lamb waves are investigated for the effects of stress on both symmetrical and anti-symmetrical modes in an aluminum plate for wave propagation and load parallel. Data are compared with those for the case of load and measurement axis perpendicular. It is the S1 mode which exhibits significantly higher sensitivity to stress than other Lamb modes. For aluminum the use of the S1 mode for stress measurement is found to be about six times more sensitive, than bulk waves, for the load-measurement axes parallel case and this compares with about ten times for the case of load-measurement axes perpendicular. Disciplines Acoustics, Dynamics, and Controls | Aerospace Engineering | Structures and Materials Comments This article is published as Pei, Ning, and Leonard J. Bond. "Comparison of acoustoelastic Lamb wave propagation in stressed plates for different measurement orientations."
Article ID: IJCIET_11_08_003 in Steel Plate using Lamb Waves
This paper detects, through numerical simulations, the stress in structures using lamb waves. The finite element model of steel plate was developed using the commercial finite element programs ABAQUS and ANSYS. Dynamic models were run for Lamb wave propagation in steel plate under the effect of different compressive and tensile stresses. The simulations have revealed that with the variation of stress there is no effect of time of flight. In the case of compressive stress, it's found that the amplitude of received wave is increased slightly with increasing of compressive stress. In otherwise of tensile stress, the amplitude of received wave is also decreased slightly with increasing of tensile stress.
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The purpose of the present report consists in studying an opportunity of use of devices for registration of complex signals in thin- walled details of structures. Lamb's wave properties were used for explanation of dynamic reaction of thin plate surface when in some place there is some source of impulse loading. The experiment on the study of some parameters of propagation of elastic waves in the plate from the Al-Cu aluminum alloy was carried out. Using the Lamb's waves' dispersion property, the formal simulation of waves interference was carried out. It was shown that dynamic reaction of thin plate surface can be explained as effect of several waves' interference. More detailed researching of the structure and the parameters of signals, excited with the impact loading, composes the basis of this work.
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