Numerical validation of isotropic and transversely isotropic constitutive models for healthy and unhealthy cerebral arterial tissues

66/2013

Numerical validation of isotropic and transversely isotropic constitutive models for healthy and unhealthy cerebral arterial tissues

Thursday 19th December 2013

Tricerri, P.; Dede ,L; Quarteroni, A.; Sequeira, A.

This paper deals with the validation of constitutive models for healthy and unhealthy cerebral arterial tissues by means of numerical simulations of static inflation tests on a cylindrical geometry representing a specimen of anterior cerebral artery. The healthy arterial tissue is described by means of isotropic and transversely isotropic models. In particular, we validate a transversely isotropic multi-mechanism law, specifically proposed for the cerebral arterial tissue, for which the recruitment of the collagen fibers occurs at finite strains. Moreover, we consider numerical simulations of unhealthy cerebral arterial tissues by taking into account the mechanical weakening of the vessel wall that occurs during early development stages of cerebral aneurysms. We study the effects of the mechanical degradation on kinematic quantities of interest, namely the stresses distribution, that are commonly related to the progressive degradation of the arterial tissue by simulating static inflation tests for both isotropic and transversely isotropic models, including the multi-mechanism law.