Effects of flow rate and blade outlet width on hemolytic performance of centrifugal blood pump / 中国组织工程研究

ABSTRACT

BACKGROUND: Hemolysis is an important problem in the design and development of artificial heart pumps. Hemolysis is associated with the shear force of blood cells in the pump and the movement time in the pump. OBJECTIVE: To analyze the relationship between the operating parameters of blood pump (flow rate of blood pump), the structure of blood pump (outlet width of blade) and the shear stress of blood cells in artificial heart pump. METHODS: The basic structure of the centrifugal blood pump was designed according to the velocity coefficient method. The three-dimensional model of the blood pump, mesh division and flow field simulation were established by using CFturbo, ANSYS ICEM and FLUENT software respectively to study the best mesh division method. The results of the numerical simulation corrected the diameter of the impeller outlet to finally obtain an artificial heart pump meeting the needs of the human heart. In order to reduce the shear stress and movement time of blood cells in the heart pump, the optimal design and analysis of the impeller inlet flow rate Q (2, 3, 4, 5, 6, 7 L/min) and the operating parameter blade outlet width b2 (2.0, 2.1, 2.2, 2.3, 2.4, 2.5 mm) of the centrifugal artificial heart pump were designed to reduce the probability of hemolysis. RESULTS AND CONCLUSION: (1) As the flow rate increased, the shear stress of the blood cells in the blood pump gradually increased, and the movement time gradually decreased. As the flow rate increased, the standard hemolysis value in the blood pump gradually decreased, and the damage to the blood cells in the blood pump alleviated. When the flow rate was 7 L/min, the standard hemolysis value in the blood pump was the lowest. (2) With the increase of blade outlet width, the shear stress of the blood in the pump decreased, and the movement time of the blood in the pump increased. When the blade outlet width was 2.0-2.5 mm, the hemolysis value in the blood pump decreased with the increase of the blade outlet width. When the blade outlet width was about 2.5 mm, the hemolysis value in the blood pump was the lowest.