Study on the influence of dynamic/static interface processing methods on CFD simulation results of the axial-flow blood pump

Computational fluid dynamics is an essential tool for the flow field analysis of the blood pump. The interface processing method between the dynamic/static regions will affect the accuracy of simulation results, but its influence on the simulation results is still unclear. In this study, the axial-flow blood pump was taken as the research object, and the effects of the mixing plane, frozen rotor, and sliding mesh methods on the following results were compared: flux conservation at the interface, hydraulic characteristics, and velocity field distribution. In parallel, the particle image velocimetry experiment was carried out to measure the velocity field of the impeller, the inlet, and the outlet area of the blood pump. The results show that the above methods have significant differences in flux conservation between the impeller and the back vane. The average surface energy flux’s error of frozen rotor and sliding mesh are 0.7% and 0.72%, respectively, while the mixing plane method reaches 3.6%. This nonconservative transfer affects the distribution of the downstream velocity field, and the velocity field predicted by the mixing plane at the outlet is quite different. It is suggested to use the frozen rotor method and the sliding mesh method in the simulation of the blood pump.

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COMPARISON AND EXPERIMENTAL VALIDATION OF TURBULENCE MODELS FOR AN AXIAL FLOW BLOOD PUMP

Journal of Mechanics in Medicine and Biology ◽

10.1142/s0219519419400633 ◽

2019 ◽

Vol 19 (08) ◽

pp. 1940063

Author(s):

SHUAI WANG ◽

JIANPING TAN ◽

ZHEQIN YU

Keyword(s):

Velocity Field ◽

Flow Field ◽

Axial Flow ◽

Turbulence Models ◽

Internal Flow ◽

Reynolds Stress Model ◽

Blood Pump ◽

Axial Flow Blood Pump ◽

Standard Formula ◽

Text Model

Computational fluid dynamics (CFD) has become an essential tool for designing and optimizing the structure of blood pumps. However, it is still questionable which turbulence model can better obtain the flow information for axial flow blood pump. In this study, the axial flow blood pump was used as the object, and the influence of the common turbulence models on simulation was compared. Six turbulence models (standard [Formula: see text]–[Formula: see text] model, RNG [Formula: see text]–[Formula: see text] model, standard [Formula: see text]–[Formula: see text] model, SST [Formula: see text]–[Formula: see text] model, Spalart–Allmaras model, SSG Reynolds stress model) were used to simulate the pressure difference and velocity field of the pump. In parallel, we designed a novel drive system of the axial flow blood pump, which allowed the camera to capture the internal flow field. Then we measured the flow field in the impeller region based on particle image velocimetry (PIV). Through the comparison of experiments and simulation results, the average errors of velocity field obtained by the above models are 30.97%, 19.40%, 24.25%, 15.28%, 28.51%, 23.00%, respectively. Since the SST [Formula: see text]–[Formula: see text] model has the smallest error, and the streamline is consistent with the experimental results, it is recommended to use SST [Formula: see text]–[Formula: see text] model for numerical analysis of the axial flow blood pump.

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