Evaluation of hemolysis within a blood pump on a computer is useful for developing rotary blood pumps. The flow fields in the axial flow blood pump were analyzed using computational fluid dynamics (CFD). A blood damage index was calculated based on the changes in shear stress with time along 937 streamlines. Hemolysis of the pumps was measured using bovine blood. A good correlation between the computed and measured hemolysis results was observed. CFD analysis is useful for estimating hemolysis of rotary blood pumps on a computer.

A low rate of hemolysis is an important factor for the development of a rotary blood pump. It is, however, difficult to identify the areas where hemolysis occurs. Computational fluid dynamics (CFD) analysis enables the engineer to predict hemolysis on a computer. In this study, fluid dynamics throughout intracardiac axial flow pumps with different designs were analyzed three-dimensionally using CFD software. The computed pressure-flow characteristics of the pump were in good agreement with the measurements. The Reynolds shear stress was computed along particle trace lines. Hemolysis was estimated on the basis of shear stress (tau) and its exposure time (Deltat): dHb/Hb = 3.62 x 10(-7)(tau)(i)(2.416) x Delta(t)(i)(0.785). Particle damage increased with time along the particle trace lines. Hemolysis of each of the pumps was measured in vitro. The computed hemolysis values were in good agreement with the experimental results. CFD is a useful tool for developing a rotary blood pump.

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This study hlvestigates sepalation connDl ushlg vortex generator jets on a test model which is s ゆ lected to favorable and adven5e pressure gradients ． The 丘nal target of this study is to control the separation on 血e a仕 一 loaded皿 bine blade in血e unsteady main flow ． The numerical simUlation is to control 止 e separation using steady vortex − jets ( VGJs ) in the steady main 且ow ． The test model has two curves to create a shape f ( 〕 r establishhlg a pressure gradient typical to an a丘 一 10aded turbine blade ． There are 7 holes ， and these holes have a 5． Omm diameter with a 30 − degree or 45 − degree pitch angle and a 90 − degree skew angle ． The 珂 ection locaUon is set at the point ofmaximum velocity on the test model ． The velocity ofthejet is且xed at 食)ur times the velocity of the maill flow ． It is found that the e価 t of separaUon control is obtailled 丘om a 45 − degree pitch angle ．