BACKGROUND Previous numerical modeling studies on red blood cell (RBC) aggregation have elucidated the inverse relationship between shear rate and RBC aggregation under steady flow. However, information on the cyclic variation in RBC aggregation under pulsatile flow remains lacking. OBJECTIVE RBC aggregation was simulated to investigate the complex interrelationships among the parameters of RBC motion under pulsatile flow. METHODS A two-dimensional particle model was used to simulate RBC motion driven by hydrodynamic, aggregation, and elastic forces in a sinusoidal pulsatile flow field. The kinetics of RBCs motion was simulated on the basis of the depletion model. RESULTS The simulation results corresponded with previously obtained experimental results for the formation and destruction of RBC aggregates with a parabolic radial distribution during a pulsatile cycle. In addition, the results demonstrated that the cyclic variation in the mean aggregate size of RBCs increased as velocity amplitude increased from 1 cm/s to 3 cm/s under a mean steady flow of 2 cm/s, as mean steady flow velocity decreased from 6 cm/s to 2 cm/s under a velocity amplitude of 1.5 cm/s, and as stroke rate decreased from 180 beats per minute (bpm) to 60 bpm. CONCLUSIONS The present simulation results verified previous experimental results and improved the current understanding of the complex spatiotemporal changes experienced by RBC aggregates during a sinusoidal pulsatile cycle.

中文翻译：

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基于耗竭模型的正弦脉动血流下红细胞聚集动力学的数值模拟。

背景技术先前关于红细胞（RBC）聚集的数值模型研究已经阐明了稳定流量下剪切速率与RBC聚集之间的反比关系。但是，仍然缺乏有关脉动血流下红细胞聚集的周期性变化的信息。目的对红细胞聚集进行模拟，以研究脉动流下红细胞运动参数之间的复杂相互关系。方法使用二维粒子模型模拟正弦脉动流场中流体动力，聚集和弹性力驱动的RBC运动。在耗尽模型的基础上模拟了RBC运动的动力学。结果模拟结果与先前获得的关于在脉动周期内具有抛物线形径向分布的RBC聚集体的形成和破坏的实验结果相对应。此外，结果表明，在平均流速为2 cm / s的情况下，随着速度振幅从1 cm / s增加到3 cm / s，RBC的平均聚集体大小的循环变化会增加，而平均流速从在1.5 cm / s的速度幅度下，速度从6 cm / s降低到2 cm / s，并且冲程频率从每分钟180次搏动（bpm）降低到60 bpm。结论本模拟结果验证了先前的实验结果，并改善了当前对正弦脉动周期中RBC聚集体经历的复杂时空变化的理解。结果表明，在平均流速为2 cm / s的情况下，随着速度振幅从1 cm / s增大到3 cm / s，RBC的平均聚集体大小的周期性变化会增加，而平均流速从6 cm / s下降到了在1.5 cm / s的速度幅度下从s降至2 cm / s，并且随着冲程频率从每分钟180次搏动（bpm）降至60 bpm。结论本模拟结果验证了先前的实验结果，并改善了当前对正弦脉动周期中RBC聚集体经历的复杂时空变化的理解。结果表明，在平均流速为2 cm / s的情况下，随着速度振幅从1 cm / s增大到3 cm / s，RBC的平均聚集体大小的周期变化会增加，而平均流速从6 cm / s下降到3 cm / s在1.5 cm / s的速度幅度下从s降至2 cm / s，并且随着冲程频率从每分钟180次搏动（bpm）降至60 bpm。结论本模拟结果验证了先前的实验结果，并改善了当前对正弦脉动周期中RBC聚集体经历的复杂时空变化的理解。并且随着中风频率从每分钟180次的搏动（bpm）降低到60次/分。结论本模拟结果验证了先前的实验结果，并改善了当前对正弦脉动周期中RBC聚集体经历的复杂时空变化的理解。并且随着中风频率从每分钟180次的搏动（bpm）降低到60次/分。结论本模拟结果验证了先前的实验结果，并改善了当前对正弦脉动周期中RBC聚集体经历的复杂时空变化的理解。