为了探究使用计算流体力学(Computational Fluid Dynamics,CFD)评估离心血泵性能时采用非定常模拟方法的必要性,对美国食品药品监督管理局(Food and Drug Administration,FDA)提供的标准模型进行数值仿真,分别使用定常单坐标系(Single R...为了探究使用计算流体力学(Computational Fluid Dynamics,CFD)评估离心血泵性能时采用非定常模拟方法的必要性,对美国食品药品监督管理局(Food and Drug Administration,FDA)提供的标准模型进行数值仿真,分别使用定常单坐标系(Single Reference Frame,SRF)与非定常动静区域耦合的滑移网格模拟方法对4个工况进行模拟并与实验结果进行对比。结果表明,定常SRF预测的泵内速度场与实验结果误差在4%以内;非定常滑移网格的误差为2%以内,且确定系数相较定常SRF平均高0.4。对于溶血系数的计算,两种方法均未给出准确的定量预测。因此对于血泵流场的计算,非定常滑移网格模型与定常SRF模型相比,有一定的准确度上的提升,但并不明显。展开更多
Objective： Hemolysis in blood pumps has been measured by various in vitro test methods, in which normalized index of hemolysis （NIH） was established. As NIH is complicated and difficult to calculate, erythrocyte fr...Objective： Hemolysis in blood pumps has been measured by various in vitro test methods, in which normalized index of hemolysis （NIH） was established. As NIH is complicated and difficult to calculate, erythrocyte fragment count is proposed in the present study to predict hemolysis in roller pumps. Methods： Five paired in vitro tests were conducted using the POLYSTAN pediatric pump（group A） and COBE pump（ group B）. Ten whole blood samples （400 ml ） were circled in the roller pump for 16 h. Erythrocyte fragments count and plasma-free hemoglobin （FHb） were measured before pumping and every two hours through circulation after four-hour-pumping. The morphological changes of erythrocyte were observed by scanning electron microscope. Results： The two groups＇ EFC and FHb levels were increased linearly during a long duration of pumping and linear regression of erythrocyte fragments count and plasma-free hemoglobin were correlated. Conclusion： Erythrocyte fragments count could be used as an index in evaluating the in vitro hemolytic properties of blood pumps.展开更多
文摘为了探究使用计算流体力学(Computational Fluid Dynamics,CFD)评估离心血泵性能时采用非定常模拟方法的必要性,对美国食品药品监督管理局(Food and Drug Administration,FDA)提供的标准模型进行数值仿真,分别使用定常单坐标系(Single Reference Frame,SRF)与非定常动静区域耦合的滑移网格模拟方法对4个工况进行模拟并与实验结果进行对比。结果表明,定常SRF预测的泵内速度场与实验结果误差在4%以内;非定常滑移网格的误差为2%以内,且确定系数相较定常SRF平均高0.4。对于溶血系数的计算,两种方法均未给出准确的定量预测。因此对于血泵流场的计算,非定常滑移网格模型与定常SRF模型相比,有一定的准确度上的提升,但并不明显。
文摘Objective： Hemolysis in blood pumps has been measured by various in vitro test methods, in which normalized index of hemolysis （NIH） was established. As NIH is complicated and difficult to calculate, erythrocyte fragment count is proposed in the present study to predict hemolysis in roller pumps. Methods： Five paired in vitro tests were conducted using the POLYSTAN pediatric pump（group A） and COBE pump（ group B）. Ten whole blood samples （400 ml ） were circled in the roller pump for 16 h. Erythrocyte fragments count and plasma-free hemoglobin （FHb） were measured before pumping and every two hours through circulation after four-hour-pumping. The morphological changes of erythrocyte were observed by scanning electron microscope. Results： The two groups＇ EFC and FHb levels were increased linearly during a long duration of pumping and linear regression of erythrocyte fragments count and plasma-free hemoglobin were correlated. Conclusion： Erythrocyte fragments count could be used as an index in evaluating the in vitro hemolytic properties of blood pumps.
