人工心脏圆盘泵的流动特性研究

Flow characteristics of disc pump used as artificial heart

人工心脏(血泵)一直存在泵体对血细胞剪切力过大和流速过快容易引起溶血的问题。为了研究人体正常血压情况下,血泵内部剪切力和速度场的分布情况,选择圆盘泵叶轮代替传统离心泵叶轮,对两种模型进行数值计算,分析不同叶轮内部剪切力和速度场的分布规律。研究表明传统离心泵内部流速高,叶片表面剪切力大,对血细胞的伤害大。圆盘泵相比传统离心泵,剪切力更小,流场速度分布均匀,流速更小。和传统离心泵相比,不同转速下圆盘泵能降低溶血的发生率。圆盘泵叶片数为6片时,抗溶血性能更好。研究结果为血泵的优化提供理论依据。

The hemolysis caused by the excessive shear force of the pump body on the blood cells and high velocity of flow has been a problem in artificial heart(blood pump).The disc pump impeller is selected to replace the traditional centrifugal pump impeller,and the two models are numerically calculated to analyze the internal shear force and velocity field of different impellers under normal human blood pressure.The results show that the traditional centrifugal pump has high internal velocity and larger shear force on blade surface,resulting in great damages to blood cells,while the disc pump has less shear force,uniform velocity distribution,and smaller velocity.Therefore,the disk pump instead of the traditional centrifugal pump can reduce the occurrence of hemolysis at different rotational speeds.When the number of blades is 6,the disc pump exhibits better performance on anti-hemolysis.The study provides a theoretical basis for the optimization of blood pump.