Children born with univentricular heart disease typically must undergo three open heart surgeries within the first 2-3 years of life to eventually establish the Fontan circulation. In that case the single working ventricle pumps oxygenated blood to the body and blood returns to the lungs flowing passively through the Total Cavopulmonary Connection (TCPC) rather than being actively pumped by a subpulmonary ventricle. A mechanical pump inserted into this circulation providing a 3-5 mmHg pressure augmentation would reestablish bi-ventricular physiology serving as a bridge-to-recovery, bridge-to-transplant or destination therapy as a "biventricular Fontan" circulation. A Viscous Impeller Pump (VIP) situated in the center of the 4-way TCPC intersection is studied here. We hypothesized that Large Eddy Simulation (LES) using high-order numerical methods is needed to capture unsteady powered and unpowered Fontan hemodynamics. Inclusion of a mechanical pump into the CFD further complicates matters due to the need to account for rotating machinery. Validation of the code is provided for an Idealized Medical Device, as well as for idealized TCPC simulations. Multiblock capabilities are added to the solver to allow for easier setup of complex geometries. Fontan hemodynamics is studied for both Unpowered and Powered cases on both Idealized and Patient specific geometries. Models to estimate blood damage and improve boundary conditions are also proposed.
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