Computational and Experimental Evaluation of the Fluid Dynamics and Hemocompatibility of the CentriMag Blood Pump

: The CentriMag centrifugal blood pump is a newly developed ventricular assist device based on magnetically levitated bearingless rotor technology. A combined computational and experimental study was conducted to characterize the hemodynamic and hemocompatibility performances of this novel blood pump. Both the three‐dimensional flow features of the CentriMag blood pump and its hemolytic characteristics were analyzed using computational fluid dynamics (CFD)‐based modeling. The hydraulic pump performance and hemolysis level were quantified experimentally. The CFD simulation demonstrated a clean and streamlined flow field in the main components of the CentriMag blood pump. The predicted results by hemolysis model indicated no significant high shear stress regions in the pump. A comparison of CFD predictions and experimental results showed good agreements. The relatively large gap passages (1.5 mm) between the outer rotor walls and the lower housing cavity walls provide a very good surface washing through a secondary flow path while the shear stresses in the secondary flow paths are reduced, resulting in a low rate of hemolysis ([Normalized Index of Hemolysis] NIH = 0.0029 ± 0.006) without a decrease of the pump’s hydrodynamic performance (pressure head: 352 mm Hg at a flow rate of 5.0 L/min and a rotational speed of 4000 rpm).