Fang Peng, Du Jianjun, Yu Shunzhou
School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China.
ShenZhen Core Medical Technology CO, LTD, Shenzhen, 518055, China.
Cardiovasc Eng Technol. 2020 Aug;11(4):337-349. doi: 10.1007/s13239-020-00464-0. Epub 2020 May 14.
The main purpose is to compare the characteristics and performance of a centrifugal blood pump with and without center post. Furthermore, to propose a center post design guide for the development of centrifugal blood pumps: finding the appropriate height and diameter of the center post.
A centrifugal blood pump with different center post configurations is investigated using Computational Fluid Dynamics (CFD) in an extensive parametric approach. Height and diameter of the center post are varied on 4 levels each. Pressure head and hydraulic efficiency curves, pressure and velocity contours and volumetric histograms of scalar shear stress (SSS) distribution are discussed in detail.
The simulation results show uniform pressure distribution around the casing in the baseline design. Although obtaining the minimum Normalized Index of Hemolysis (NIH), average scalar shear stress (ASSS), and volumetric percentage ratios (SSS > 9, 50 and 150 Pa), a stagnation and recirculation zone in the impeller eye above the casing bottom is detected in center post free (H = 0 mm) pump. With the establishment and further increase of the center post height, the stagnation zone disappears gradually. The results also indicate that flow recirculation and stagnation around the circumference of the center post occurs when the center post has a small diameter. As the diameter increases, a reversed flow is formed between the impeller and the center post.
The center post can greatly reduce the stagnation zone occurring in the center post free pump. The diameter of center post makes a difference to the flow field in the gap between the impeller and the center post.
主要目的是比较有无中心柱的离心式血泵的特性和性能。此外，为离心式血泵的研发提出中心柱设计指南：确定中心柱的合适高度和直径。
采用计算流体动力学（CFD），通过广泛的参数化方法研究具有不同中心柱配置的离心式血泵。中心柱的高度和直径各在4个水平上变化。详细讨论了压头和水力效率曲线、压力和速度等值线以及标量剪切应力（SSS）分布的体积直方图。
模拟结果表明，在基线设计中，泵壳周围的压力分布均匀。尽管无中心柱（H = 0 mm）的泵获得了最低的溶血归一化指数（NIH）、平均标量剪切应力（ASSS）和体积百分比（SSS＞9、50和150 Pa），但在泵壳底部上方的叶轮入口处检测到一个停滞和再循环区域。随着中心柱高度的建立和进一步增加，停滞区域逐渐消失。结果还表明，当中心柱直径较小时，中心柱周围会出现流动再循环和停滞。随着直径的增加，在叶轮和中心柱之间形成逆流。
中心柱可大大减少无中心柱泵中出现的停滞区域。中心柱的直径对叶轮和中心柱之间间隙中的流场有影响。
