Torsional vibrations of infinite composite poroelastic cylinders

Abstract

A study of torsional vibrations of an infinite composite poroelastic circular solid cylinder made of two different materials is made. The frequency equation of such torsional vibrations is obtained following analytical model based on Biot’s theory of wave propagation in liquid saturated porous media. Each dilatation of the solid and the liquid media is zero and therefore the frequency equation of torsional vibrations is same for pervious and impervious surfaces. The plots of non-dimensional frequency versus ratio of thickness of casing to the wavelength for two composite poroelastic cylinders are presented, and then discussed. The displacements of second and third torsional modes are determined and presented graphically for the ratio of radius of composite poroelastic solid cylinder to the radius of the inner solid cylinder. Results of previous works are shown as special case of the present analysis. By ignoring liquid effects, the results of purely elastic solid are obtained.

International Journal of Engineering, Science and Technology, Vol. 2, No. 6, 2010, pp. 150-161