Shanghai Key Laboratory of Multiphase Flow and Heat Transfer in Power Engineering, School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai, China.
Department of Mechanical and Aerospace Engineering, The Hong Kong University of Science and Technology, Hong Kong.
Int J Artif Organs. 2022 Dec;45(12):1028-1036. doi: 10.1177/03913988221114156. Epub 2022 Aug 26.
In order to reduce the blood damage of an artificial heart pump and optimize its hydraulic performance, a centrifugal blood pump with superhydrophobic characteristics is proposed in this study.
To study the influence of superhydrophobic surface characteristics on the performance of centrifugal blood pumps, the Navier slip model is used to simulate the slip characteristics of superhydrophobic surfaces, which is realized by the user defined function of ANSYS fluent. The user defined functions with different values of slip length are verified by two benchmark solutions of laminar flow and turbulence in the pipeline. The blood pump model adopts the designed centrifugal blood pump, and its head, hydraulic efficiency and hemolysis index are calculated. The Navier slip boundary condition (a constant slip-length of 50 μm) is applied to the walls of the blood pump impeller and a volute at different positions, and the influence of the superhydrophobic surface on the performance of the blood pump at the design point = 6 L/min was compared and analyzed.
The results show that the centrifugal blood pump model used in this paper has good blood compatibility and meets the design requirements; the superhydrophobic surface can significantly reduce the scalar shear stress in the blood pump. At the design point, when the slip length is 50 μm, the mass-average scalar shear stress in the impeller area and the volute area reduction rate is about 5.9%, the hydraulic efficiency growth rate is about 3.8%, the hemolysis index reduction rate is about 18.4%, and the pressure head changes little with a growth rate of 0.3%.
Centrifugal blood pumps with superhydrophobic surfaces can improve the efficiency of blood pumps and reduce hemolysis. Based on these encouraging results, vitro investigations for actual blood damage would be practicable.
为了降低人工心脏泵的血液损伤并优化其水力性能，本研究提出了一种具有超疏水特性的离心泵。
为了研究超疏水表面特性对离心泵性能的影响，使用纳维滑动模型来模拟超疏水表面的滑动特性，这是通过 ANSYS fluent 的用户自定义函数来实现的。使用不同滑动长度的用户自定义函数通过管道中两种层流和湍流的基准解进行验证。血液泵模型采用设计的离心泵，计算其扬程、水力效率和溶血指数。纳维滑动边界条件（恒定滑动长度为 50μm）应用于血液泵叶轮和蜗壳的不同位置的壁面，比较和分析超疏水表面对设计点=6L/min 时血液泵性能的影响。
结果表明，本文中使用的离心泵模型具有良好的血液相容性，符合设计要求；超疏水表面可以显著降低血液泵中的标量剪切应力。在设计点，当滑动长度为 50μm 时，叶轮区域和蜗壳区域的质量平均标量剪切应力降低率约为 5.9%，水力效率增长率约为 3.8%，溶血指数降低率约为 18.4%，压力头变化很小，增长率为 0.3%。
具有超疏水表面的离心泵可以提高血液泵的效率并降低溶血。基于这些令人鼓舞的结果，实际血液损伤的体外研究将是可行的。
