Finite Element Analysis of Aortic Mechanics

To validate our finite element analysis, we used our 3D-aortic wall model to reproduce published simulation results according to the boundary conditions of respective studies. Our model using COMSOL Multiphysics 5.3a was able to replicate results published by Roccabianca et al.^{18 (link)}, Baek et al.^{28 (link)} and de Gelidi et al.^{29 (link)}. Markers in Fig. 5 represent data reported in Roccabianca’s study^{18 (link)}. The authors simulated biaxial loading protocols of the descending thoracic aorta (material test data by García-Herrera et al.^{30 (link)} with circumferential to axial stress ratio of 1:2, 1:1 and 2:1. Reproduced values using our aortic wall model are plotted as solid lines (Fig. 5), showing averages of circumferential and axial Cauchy stresses across representative central cut planes. Our validation provided good overall correlation with slight deviations for minimal aortic wall strains.Figure 5

Model validation via biaxial Cauchy stress–stretch data evaluated for three different loading protocols (ratio circumferential to axial stress). Markers represent results reported in Roccabianca et al.^{18 (link)}. Solid lines were obtained by inflation tests of aortic wall model employing the identical constitutive equation and concomitant best-fit parameters.