Investigation of the influence of centrifugal pump wet part geometry on hemolysis index

The present study focuses on the influence of the circulatory support pump wet part geometry on the level of damage experienced by blood cells in it. The object of the study is a centrifugal pump: axial input, impeller and volute. The values of density and viscosity are constant and are close to the physiological parameters of blood of a healthy human. In order to estimate hemolysis blood cells are considered as spherical particles, which do not interact with each other. At each point of the trajectory of the particle equivalent shear stress is calculated according to Huber-Mises criterion. Hemolysis is then calculated in accordance with Lagrangian approach to particle movement in a flow. As an experimental hemolysis curve a power law of equivalent shear stress depending on the time the particle has experienced this stress was chosen. For a wet part optimization criterion of maximum efficiency and minimum hemolysis are considered.