Computational fluid dynamics and experimental validation of a microaxial blood pump

Area of Science:

• Biomedical Engineering
• Fluid Dynamics
• Medical Devices

Background:

• Minimally invasive heart assist devices, such as microaxial blood pumps, face significant design constraints due to size limitations.
• Understanding the intricate hemodynamics within these pumps is crucial for optimizing performance and minimizing adverse effects like blood trauma and thrombus formation.

Purpose of the Study:

• To analyze the hemodynamics in the inlet, vane, and outlet regions of a microaxial blood pump used as an intraaortic left ventricular assist device.
• To validate computational fluid dynamics (CFD) models against experimental data for improved pump design and efficiency.

Main Methods:

• Utilized computational fluid dynamics (CFD) to model and compute flow within the microaxial blood pump.
• Employed 3-dimensional (3-D) particle tracking velocimetry (PTV) in a mock loop setup for experimental flow visualization and data acquisition.
• Compared CFD-predicted pump performance characteristics (head/flow, pressure distribution, swirl) with measured data.

Main Results:

• CFD model predictions for pump performance characteristics showed high accuracy when compared with experimental measurements.
• The CFD model accurately predicted inlet and outlet swirl, crucial parameters for pump efficiency and blood flow behavior.
• Experimental data from 3-D PTV validated the CFD simulations, confirming the model's reliability.

Conclusions:

• CFD is a valuable and accurate tool for analyzing the complex hemodynamics of microaxial blood pumps.
• The study provides insights into optimizing pump design for enhanced efficiency and reduced blood trauma in ventricular assist devices.
• Recommendations are provided regarding boundary condition definitions and spatial discretization for accurate CFD simulations in similar applications.