VISCOELASTIC MODEL FOR ARTERIAL-WALL MATERIALS

Considering that the arteries are subjected to a large initial static deformation and a small dynamical displacement field superposed on this initial deformation, in physiological conditions, in this work we have presented a Kelvin-Voigt type of viscoelastic model for such soft tissues. For its simplicity in the analysis the material is assumed to be isotropic, incompressible and constitutionally nonlinear in Finger deformation tenser but linear in deformation rate tenser. In order to obtain the numerical values of the material constants appearing in the constitutive relations, the solutions of two illustrative problems, namely, the radial inflation and the axial stretch of a cylindrical tube and the propagation of torsional waves in a prestressed cylindrical bar, are given. By comparing the result of the first problem by the experimental results of Simon et al. [13] we have determined the numerical values of elastic coefficients. Having solved the latter problem we have proposed a method to determine the viscoelastic coefficients.