The present paper deals with the propagation of torsional waves in a composite poroelastic circular cylinder consisting of two concentric poroelastic layers joined together with a thin flexible bond. The composite cylinder is made of two concentric layers made of different poroelastic materials each of which is homogenous and isotropic. The frequency equation of torsional vibrations is obtained which is same for pervious and impervious surfaces. The torsional wave propagation is seen to be affected by the presence of bonding material apart from the material parameters of the composite cylinder. Particular cases are considered under different assumptions. Frequency as a function of wave number is presented graphically for different types of poroelastic materials and discussed. Generally, it is seen that the frequency of torsional wave is higher in composite cylinder-II than that of composite cylinder-I. Also it is observed that the first mode in composite cylinder-I is not dispersive while the other modes in composite cylinder-I as well as the first three modes in composite cylinder-II are dispersive. The results of previous studies are obtained as a particular case of present investigation.
展开▼
