(340c) Blood Damage Predictions Using Computational Fluid Dynamics of Blood Flow through a Bi-Leaflet Prosthetic Heart Valve

Authors: 
James, M., University of Oklahoma
O'Rear, E. A., University of Oklahoma
Papavassiliou, D. V., The University of Oklahoma
Artificial heart valves can be invaluable to addressing heart defects and diseases. However, these prosthetic devices expose the blood to unnatural turbulent flow conditions. This non-uniform flow exposes blood to high stress, which can damage the blood cells. The purpose of this research is to analyze blood flow in artificial heart valves and develop a new approach to predict the damage (hemolysis) caused to red blood cells (RBCs) due to the intensity and extent of turbulence. Using ANSYS ICEM CFD, a virtual bi-leaflet prosthetic heart valve was constructed and meshed. To compare the amount of damage in a working and malfunctioning valve, a similar valve, but with one closed leaflet, was also created. The simulations and calculations at different Reynold numbers and stress conditions are then done in ANSYS Fluent and validated with experimental findings in the literature. Results from the CFD simulations provide the spatial distribution of Kolmogorov length scales that are used for eddy analysis [1,2] in the heart valves. The Kolmogorov length scale (KLS), or the dissipative length scale, is used to find the size of eddies in the fluid. This CFD research enables approximation of the number and shape of eddies in the blood as a possible causation or correlation to the amount of damage to the blood cells.

Keywords: Computational Fluid Dynamics, Heart Valve, Blood Flow, Hemolysis, Eddy Analysis

References

  1. M. Ozturk et al., "Hemolysis Related to Turbulent Eddy Size Distributions Using Comparisons of Experiments to Computations",Artificial Organs (2015), 39(12): E227-E239.
  2. M. Ozturk et al., "An Approach for Assessing Turbulent Flow Damage to Blood in Medical Devices", J Biomech Eng (2017), 139(1), 011008.