Simulating the mechanical response of artery walls by high order finite elements
Prof. Zohar YosibashJan. 14, 2011, 1:30 p.m. K 153C
The healthy human artery wall is a complex biological structure whose mechanical response is of major interest and attracted a significant amount of research, mainly related to its passive response. Herein we present a high-order FE method for the treatment of the compressible hyper-elastic constitutive model for the passive response based on a transversely isotropic strain-energy-density-function (SEDF). More specifically, we first address two variants of the SEDF and augment it by a volumetric part which is neglected in most studies.
Numerical examples are provided to demonstrate the efficiency of the high-order methods compared to classical h-FEMs, and thereafter the influence of the slight compressibility on the results. Although the active response (when smooth muscle cells are activated) has a significant influence of the overall mechanical response of the artery wall, it has been scarcely investigated because of the difficulty of representing such an influence in a constitutive model and lack of experimental evidence that can validate such models. This active response is strongly coupled with the passive response because of the mutual interaction (smooth muscle cells react as a function of the mechanical response). In this presentation, we provide experimental evidence of the strong influence of the active response and propose different approaches for its implementation using high-order FE methods.