On torsional vibrations of axial-symmetric infinite hollow poroelastic cylinders

Using Biot viscosity-extended theory, this work gives a methodology to obtain analytical formulas for the torsional phase velocities and torsional attenuations in fully saturated, homogeneous, isotropic, axially symmetric hollow poroelastic cylinders with stress-free boundary conditions on both surfaces. These phase velocities and attenuations formulas are given in terms of the poroelastic medium, such as porosity, permeability, solid density, fluid shear viscosity, and solid-frame shear modulus, among others. We use computational simulations to compare how torsional waves propagate in axial symmetric hollow cylinders in Biot viscosity-extended theory and Biot’s theory. A comparison of torsional wave propagation in hollow and solid cylinders is also provided.