Investigation of material modeling in fluid–structure interaction analysis of an idealized three-layered abdominal aorta: aneurysm initiation and fully developed aneurysms

Abstract

Different material models for an idealized three-layered abdominal aorta are compared using computational techniques to study aneurysm initiation and fully developed aneurysms. The computational model includes fluid-structure interaction (FSI) between the blood vessel and the blood. In order to model aneurysm initiation, the medial region was degenerated to mimic the medial loss occurring in the inception of an aneurysm. Various cases are considered in order to understand their effects on the initiation of an abdominal aortic aneurysm. The layers of the blood vessel were modeled using either linear elastic materials or Mooney-Rivlin (otherwise known as hyperelastic) type materials. The degenerated medial region was also modeled in either linear elastic or hyperelastic-type materials and assumed to be in the shape of an arc with a thin width or a circular ring with different widths. The blood viscosity effect was also considered in the initiation mechanism. In addition, dynamic analysis of the blood vessel was performed without interaction with the blood flow by applying time-dependent pressure inside the lumen in a three-layered abdominal aorta. The stresses, strains, and displacements were compared for a healthy aorta, an initiated aneurysm and a fully developed aneurysm. The study shows that the material modeling of the vessel has a sizable effect on aneurysm initiation and fully developed aneurysms. Different material modeling of degeneration regions also affects the stressstrain response of aneurysm initiation. Additionally, the structural analysis without considering FSI (called noFSI) overestimates the peak von Mises stress by 52% at the interfaces of the layers.

Finite Element Analysis-Based Approach for Prediction of Aneurysm-Prone Arterial Segments

“…We therefore speculated that arterial wall thickness or value of von Mises stress independently are unlikely to be responsible for the predisposition of an arterial segment to aneurysm development; however, both of these parameters determine high-risk sites when combined. Indeed, it is well recognized that thin areas at high stress in the arterial wall are responsible for the development of aneurysms [24][25][26]. Importantly, we identified these aneurysm-prone arterial segments with a relatively high frequency.…”

Targeted Drug Delivery of Microbubble to Arrest Abdominal Aortic Aneurysm Development: A Simulation Study Towards Optimized Microbubble Design

“…used for describe the mechanical properties of the arterial wall. The strain energy density function is as follows 36 : where W iso is the strain energy density of the material, C 10 and C 20 are the material constants, I 1 is the first deviatoric strain invariant, J is the ratio of the deformed elastic volume over the undeformed volume materials and d is the material incompressibility parameter. The AAA wall mechanical properties have been shown in Table 1.…”

Dynamic responses of composite structures coupled through fluid medium

“…Furthermore, a structure may contact fluids on both of its sides. Some examples of internal fluids are blood flow in blood vessels (Di Martino et al 2001;Simsek and Kwon 2015), flow-induced vibration (Blevins 1977;Weaver et al 2000), sloshing motions in storage tanks under seismic loading (Chen et al 1996;Karamanos et al 2006), and hydrodynamic ram effect (Kwon et al 2016;). An example of external fluids is structural behavior subjected to underwater explosion (Kwon and Fox 1993;Walter et al 2013).…”