A reduced-dimensional model for near-wall transport in cardiovascular flows.
A reduced-dimensional model for near-wall transport in cardiovascular flows.
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DOI：
10.1007/s10237-015-0719-4
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发表时间：
2016-06
影响因子：
3.5
通讯作者：
Shadden SC
中科院分区：
文献类型：
--
作者：
Hansen KB;Shadden SC
近壁物质运输在许多心血管过程中发挥着重要作用，包括动脉粥样硬化的引发、内皮细胞血管调节和血栓形成。这些问题的特点是佩克莱特数和施密特数大以及空间和时间尺度范围广，所有这些都带来了计算困难。在这项工作中，我们建立了高施密特数流的流场和近壁质量传递之间的分析关系。这使得可以开发位于余维一容器壁表面上的壁剪应力驱动的输运方程，从而显着降低解决输运问题的计算成本。针对反应速率限制和传输限制的情况开发了该方程的单独版本，并将理想化腹主动脉瘤的数值结果与通过求解整个域上的完整传输方程获得的结果进行比较。反应速率限制模型与预期结果很好地匹配。传输限制模型在已发展的流动区域中是准确的，但过度预测了流动中入口区域和重新附着点的壁通量。
Near-wall mass transport plays an important role in many cardiovascular processes, including the initiation of atherosclerosis, endothelial cell vasoregulation, and thrombogenesis. These problems are characterized by large Péclet and Schmidt numbers as well as a wide range of spatial and temporal scales, all of which impose computational difficulties. In this work, we develop an analytical relationship between the flow field and near-wall mass transport for high-Schmidt-number flows. This allows for the development of a wall-shear-stress-driven transport equation that lies on a codimension-one vessel-wall surface, significantly reducing computational cost in solving the transport problem. Separate versions of this equation are developed for the reaction-rate-limited and transport-limited cases, and numerical results in an idealized abdominal aortic aneurysm are compared to those obtained by solving the full transport equations over the entire domain. The reaction-rate-limited model matches the expected results well. The transport-limited model is accurate in the developed flow regions, but overpredicts wall flux at entry regions and reattachment points in the flow.