Puleri Daniel F, Roychowdhury Sayan, Ames Jeff, Randles Amanda
Annu Int Conf IEEE Eng Med Biol Soc. 2020 Jul;2020:2299-2302. doi: 10.1109/EMBC44109.2020.9176313.
The fluid dynamics of microporous materials are important to many biomedical processes such as cell deposition in scaffold materials, tissue engineering, and bioreactors. Microporous scaffolds are frequently composed of suspensions of beads that have varying topology which, in turn, informs their hydrodynamic properties. Previous work has shown that shear stress distributions can affect the response of cells in microporous environments. Using computational fluid dynamics, we characterize localized differences in fluid flow attributes such wall shear stress and velocity to better understand the fluid dynamics underpinning microporous device function. We evaluated whether bead packings with similar void fractions had different fluid dynamics as characterized by the distribution of velocity magnitudes and wall shear stress and found that there are differences despite the similarities in void fraction. We show that another metric, the average distance to the nearest wall, can provide an additional variable to measure the porosity and susceptibility of microporous materials to high shear stress. By increasing our understanding of the impact of bead size on cell scaffold fluid dynamics we aim to increase the ability to predict important attributes such as loading efficiency in these devices.
微孔材料的流体动力学对许多生物医学过程都很重要，比如细胞在支架材料中的沉积、组织工程和生物反应器。微孔支架通常由具有不同拓扑结构的珠子悬浮液组成，这反过来又决定了它们的流体动力学特性。先前的研究表明，剪切应力分布会影响细胞在微孔环境中的反应。通过计算流体动力学，我们表征了流体流动属性（如壁面剪切应力和速度）的局部差异，以更好地理解支撑微孔装置功能的流体动力学。我们评估了具有相似孔隙率的珠子填充物是否具有不同的流体动力学特性（以速度大小和壁面剪切应力分布为特征），结果发现尽管孔隙率相似，但仍存在差异。我们表明，另一个指标——到最近壁面的平均距离，可以提供一个额外的变量来衡量微孔材料的孔隙率和对高剪切应力的敏感性。通过加深对珠子尺寸对细胞支架流体动力学影响的理解，我们旨在提高预测这些装置中诸如加载效率等重要属性的能力。
