Flow Evaluation and Hemolysis Analysis of BVAD Centrifugal Blood Pump by Computational Fluids Dynamics

Abstract

Computational fluid dynamics (CFD) and particle image velocimetry (PIV) are commonly used techniques to evaluate the flow characteristics in the development stage of blood pumps. CFD technique allows rapid change to pump parameters to optimize the pump performance without having to construct a costly prototype model. These techniques are used in the construction of a bi-ventricular assist device (BVAD) which combines the functions of LVAD and RVAD in a compact unit. The BVAD construction consists of two separate chambers with similar impellers, volutes, inlet and output sections. To achieve the required flow characteristics of an average flow rate of 5 l/min and different pressure heads (left -100mmHg and right -20mmHg), the impellers were set at different rotating speeds. From the CFD results, a six-blade impeller design was adopted for the development of the BVAD. It was also observed that the fluid can flow smoothly through the pump with minimum shear stress and area of stagnation which are related to haemolysis and thrombosis. Based on the compatible Reynolds number the flow through the model was calculated for the left and the right pumps. As it was not possible to have both the left and right chambers in the experimental model, the left and right pumps were tested separately.

Flow Stability in a Miniature Centrifugal Pump under the Periodic Pulse Flow

“…Regions with large magnitudes of K are more unstable than those with low magnitudes of K, and the position with the maximum K max is the most dangerous position in terms of initiating instability. For a given flow, Dou [15][16][17][18][19] proposed that the K can be expressed as follows for shear-driven flows,…”

“…Qian et al [13], Xin et al [14], and Bumrungpetch et al [15] conducted a series of works to obtain a pulsating pump with low hemolytic blood flow and a better flow stability in blood pump. They stressed that it is important to study the pulsatile flow in terms of differences in hydraulic performance between the pulsatile and non-pulsatile ventricular assisting devices.…”

2D and 3D Mechanobiology in Human and Nonhuman Systems

“…Biofluid mechanics plays a major role in a wide range of applications, including advancing research in the analysis, diagnosis, and treatment of many cardiovascular diseases and complications. As one of the most studied biofluids, blood and its flow through the body continue to be investigated through many methods, including computational models that are used to develop artificial heart pumps, valves, and dialysis machines. − A specific biofluid of interest is sickle-celled blood. Sickle cell anemia is an inherited blood disorder in which a patient’s red blood cells can be misshapen into a sickle shape, causing hemolysis (rupture) of these cells.…”