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Numerical simulation of fundamental elastic wave modes coupling in composite plates

Barski Marek, Stawiarski Adam, Chwał Małgorzata, Augustyn Marcin

Vibrations in Physical Systems

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2023

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Vol. 34, nr 1

art. no. 2023120

EN

In the case of the piezoelectric actuators of the cube-shaped installed symmetrically and perfectly bonded on both external surfaces of the plate-like structures, the symmetric and shear horizontal elastic wave modes are excited at the same time. The current work concerns the numerical simulation of the coupling of the above-mentioned elastic wave modes in a composite plate of angle ply configuration. In the first step, the dispersion curves for all studied composite configurations are estimated. Next, for the arbitrary chosen fixed frequency of the excitation, finite element simulations are performed. As a result of these simulations, the group velocities of the observed elastic modes are estimated. Next, the appropriate wave modes are identified by the comparison of the group velocities obtained from the analysis of the dispersion curves and from the simulations. In the cases for which the identification is possible, a good agreement between analytical and simulation results is observed.

2

The influence of the configuration of the fiber-metal laminates on the dispersion relations of the elastic wave modes

Barski Marek, Muc Aleksander, Stawiarski Adam

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020202

EN

The current work is devoted to the determination of dispersion curves for elastic wave modes. The studied elastic waves propagate across metal-fiber hybrid composites. In order to solve the problem, special software has been developed with the use of C++. This software works with the MS Windows operating system and the proposed solution is based on the multi-threading mechanism. It makes possible to significantly speed up the calculations. The relatively new approach is used namely the stiffness matrix method. At the very beginning, the dispersion curves are determined for the traditional composite materials of cross-ply configuration, for which the layers are made of glass fiber/epoxy resin and carbon fiber/epoxy resin. The impact of the total number of layers on the dispersion curves is investigated. Next, the influence of the thickness of the layers, which are made of aluminum alloy, on the dispersion characteristic is studied. In the second case, it is assumed that the total thickness of the composite material wall for all cases is identical.

3

Experimental study on fatigue failure evolution in composite plate monitored by wave propagation method

Stawiarski Adam, Barski Marek, Muc Aleksander

Vibrations in Physical Systems

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2020

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Vol. 31, nr 2

art. no. 2020227

EN

In this study, the elastic wave propagation method is used to observe the initiation and evolution of the fatigue failure form in the multilayered composite plate with an elliptical hole. The experimental tests with the use of active, pitch-catch elastic wave measurement techniques are used during the fatigue test of the composite specimens. The fatigue tests were preceded by the numerical, finite element analysis of the elastic wave propagation phenomenon in a composite plate with an elliptical hole. The sequential measurement related to the number of cycles during the fatigue tests was assumed. The time of flight (ToF) and amplitude change was monitored by piezoelectric sensors localized in the area of predictable failure form evolution. The analysis of the dynamic response of the structure under fatigue loading conditions by a relatively small number of piezoelectric transduces allows us to build cost-effective Structural Health Monitoring (SHM) system for damage detection and monitoring of the failure form evolution.