Computational Design of Vibration Pumping Device for Artificial Heart

To develop the prototype vibration pumping device for an artificial heart (Hashimoto et al., 1994, ASME J. Fluids Eng., 116, pp. 741-745), the flow patterns in the casing were analyzed experimentally and numerically from the viewpoint of biomechanical engineering. Considering not only the mechanical performance of the pump, but also the hemolysis, was very important to design the artificial heart. In the present study, the curvilinear coordinate transformation technique and the finite difference technique were used to numerically solve the unsteady, incompressible, and axisymmetric Navier-Stokes equations for the flow field in the various casing configurations of the vibration pumping device. The validity of numerical analysis was confirmed by comparison with the experimental data obtained by the flow visualization technique. Furthermore, the strong dependence of the hemolysis on the flow patterns in the casing was recognized. In particular, the relationship between the vorticity field in the casing and the hemolysis was elucidated. The results obtained here would provide the useful suggestions for future research and the basic design concept of vibration pumping device for the left ventricular assist device.