Dispersion of Flexural Waves in Polymer-Viscoelastic Material Pipelines

This paper is about propagating of the bending waves on the pipes which are used in non-destructive inspection of offshore oil pipelines made from viscoelastic materials to protect from corrosion. The investigations were made using exact equations of the viscoelasticity theory in the context of a piecewise homogeneous body model. The constitutive equations of the pipe were obtained through fractional exponential operators for use in numerical investigations. For the dispersive attenuation cases, the first mode results of the waveguide propagation were obtained. According to the results obtained, it was found that the increase of the viscoelasticity of the pipe material caused the decrease of the propagation velocity of the bending waves. At the same time, it is observed that the ratio between the pipe inner diameter and the wall thickness of the pipe plays an important role in wave propagation