A fluid-structure interaction analysis of the human aortic arch under inertial load

Presented is an investigation into the use of numerical methods for modelling the effects of inertial load on the human cardiovascular system. An anatomically correct geometry was developed based on three-dimensional computed tomography (CT) data and independent meshes were created for the solid and fluid regimes. These domains were simulated using independent solvers and subsequently coupled using an intermediate data transfer alogrithm. At the inlet of the arch, a pulsatile velocity boundary condition was enforced replicating the cardiac cycle. Time invariant, resistive boundary conditions were used at all outlets and a linear isotropic constitutive model was used for tissue response. Verification was conducted by comparing simulation results at standard earth gravity (9.81 m/s²) with published values for velocity, mass flow rate, deformation, and qualitative flow behaviour. The presented fluid-structure interaction (FSI) model shows strong agreement with accepted normal values. Inertial load was then applied along the longitudinal axis of the arch in multiples of standard gravity to a maximum of 8+Gz. This load increased arch flow velocities, and reduced mass flow in the ascending brachiocephalic and carotid arteries. Blood flow from the arch to the upper body and brain ceased near 8+Gz. Although the presented results are preliminary, the feasibility of such an analysis has been successfully demonstrated.