The poro-elastic behavior of a gel thin tube

The dynamics of a thin bi-phasic tube immersed in a bath and submitted to an instantaneous increment of internal pressure is analyzed by means of an analytical continuum model. The equation of motion is solved with boundary and initial conditions appropriate for the creep of the poro-elastic tube wall. The model shows that the wall relaxation time depends on the square of its thickness. The deformation of the gel matrix generates an electric potential within the tube wall with an electric field peak localized at their surfaces at the beginning of the pressure increase step. The strain field, the pressure field of interstitial fluid and the electric field across the vessel wall are derived as a function of time. The analytical treatment also elucidates the dependence of the electric field inside the gel tube on the material parameters. D 2003 Elsevier B.V. All rights reserved.