Application of CFX to Implantable Rotary Blood Pumps Suspended by Magnetic Bearings
The University of Virginia has been utilizing CFX series software to design and analyze implantable rotary blood pumps for several years. Besides the basic computational fluid dynamics (CFD) calculations and simulations of fluid field for blood pumps, several advanced CFD models were used which were relevant to the analysis of blood pumps or magnetic bearings. A Lagrangian Particle Tracking study allowed quantitative predictions of the hemolysis (breakup of red blood cells) due to the relative high shear stress. Fluid forces and moments were calculated for the magnetic bearing design. A heat transfer study was performed to investigate the temperature rises in the blood through the pumps and surrounding tissues. A transient simulation was used to study the effects of pulsatile blood flow due to the heartbeat. The microsized geometry of the pump made the choice of turbulence models significant for the accuracy of calculation. CFD results for different turbulence models were compared with Particle Image Velocimetry (PIV) experimental data. The comparison showed that the k-ω model gave better predictions of the shear level within the near wall regions than the k-ε model.