Modeling wave propagation in damped waveguides of arbitrary cross-section
نویسندگان
چکیده
In this paper the Semi-Analytical Finite Element (SAFE) method for modeling guided wave propagation is extended to account for linear viscoelastic material damping. Linear viscoelasticity is introduced by allowing for complex stiffness constitutive matrices for the material. Dispersive characteristics of viscoelastic waveguides, such as phase velocity, attenuation, energy velocity and cross-sectional wavestructures are extracted. Knowledge of the above-mentioned dispersive properties is important in any structural health monitoring attempt that uses ultrasonic guided waves for long range inspection. The proposed damped formulation is applied to several waveguides with different mechanical and geometric properties. In particular, a viscoelastic isotropic plate, a railroad track and a pipe are studied.
منابع مشابه
Modeling guided wave propagation for structural health monitoring applications
In this paper a Semi-Analytical Finite Element (SAFE) method for modeling wave propagation in waveguides of arbitrary cross-section is discussed. The method requires the finite element discretization of the cross-section of the waveguide by assuming harmonic motion along the wave propagation direction. The general SAFE technique is extended to account for viscoelastic material damping by allowi...
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