Combined extension and torsion of a swollen cylinder within the context of mixture theory

Abstract

The problem of a cylindrical mixture of a nonlinearly elastic solid and an ideal fluid subjected to combined finite axial extension and torsion is considered. In previous work, a ‘universal relation’ has been presented by assuming a small angle of twist. In this work, the general problem for the finite deformation of the swollen cylinder is discussed in the context of Mixture Theory. Computational results for the variation of the radial and tangential stretch ratios and the distribution of the fluid in the swollen deformed state are presented. The results demonstrate that the swollen volume of a cylinder reduces with twisting when the axial stretch ratio is held constant. Computational results for the reduction in the swollen volume predict the same qualitative and quantitative trends as observed in experimental results.