血流在可变形冠状动脉分又处和非平面分支中的数值研究。

Numerical investigation of blood flow in a deformable coronary bifurcation and non-planar branch.

机构信息

Faculty of Mechanical Engineering, University of Tabriz, Tabriz, Iran ; Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz Iran.

Faculty of Electrical and Computer Engineering, University of Tabriz, Tabriz, Iran.

出版信息

Bioimpacts. 2014;4(4):199-204. doi: 10.15171/bi.2014.017. Epub 2014 Dec 30.

Abstract

INTRODUCTION

Among cardiovascular diseases, arterials stenosis is recognized more commonly than the others. Hemodynamic characteristics of blood play a key role in the incidence of stenosis. This paper numerically investigates the pulsatile blood flow in a coronary bifurcation with a non-planar branch. To create a more realistic analysis, the wall is assumed to be compliant. Furthermore, the flow is considered to be three-dimensional, incompressible, and laminar.

METHODS

The effects of non-Newtonian blood, compliant walls and different angles of bifurcation on hemodynamic characteristics of flow were evaluated. Shear thinning of blood was simulated with the Carreau-Yasuda model. The current research was mainly focused on the flow characteristics in bifurcations since atherosclerosis occurs mostly in bifurcations. Moreover, as the areas with low shear stresses are prone to stenosis, these areas were identified.

RESULTS

Our findings indicated that the compliant model of the wall, bifurcation's angle, and other physical properties of flow have an impact on hemodynamics of blood flow. Lower wall shear stress was observed in the compliant wall than that in the rigid wall. The outer wall of bifurcation in all models had lower wall shear stress. In bifurcations with larger angles, wall shear stress was higher in outer walls, and lower in inner walls.

CONCLUSION

The non-Newtonian blood vessels and different angles of bifurcation on hemodynamic characteristics of flow evaluation confirmed a lower wall shear stress in the compliant wall than that in the rigid wall, while the wall shear stress was higher in outer walls but lower in inner walls in the bifurcation regions with larger angles.

摘要

简介

在心血管疾病中,动脉狭窄比其他疾病更为常见。血液的动力学特征在狭窄的发生中起着关键作用。本文数值研究了具有非平面分支的冠状动脉分叉处的脉动血流。为了进行更现实的分析,假设壁是顺应性的。此外,假定流动是三维、不可压缩和层流的。

方法

评估了非牛顿血液、顺应性壁和分叉角度对流动动力学特性的影响。使用 Carreau-Yasuda 模型模拟血液的剪切稀化。本研究主要集中在分叉处的流动特性上,因为动脉粥样硬化大多发生在分叉处。此外,由于低剪切应力区域容易发生狭窄,因此确定了这些区域。

结果

我们的研究结果表明,壁的顺应模型、分叉角度和其他流动物理性质对血流动力学有影响。在顺应性壁中观察到的壁剪切应力低于刚性壁中的壁剪切应力。在所有模型中,分叉的外壁都有较低的壁剪切应力。在角度较大的分叉处,外壁的壁剪切应力较高,内壁的壁剪切应力较低。

结论

对血流动力学特性的评价表明,顺应性血管和不同角度的分叉会导致壁剪切应力降低,而在角度较大的分叉处,外壁的壁剪切应力较高,内壁的壁剪切应力较低。

https://cdn.ncbi.nlm.nih.gov/pmc/blobs/f6f6/4298711/07512e4f3e54/BI-4-199-g001.jpg

文献AI研究员

20分钟写一篇综述,助力文献阅读效率提升50倍

立即体验

用中文搜PubMed

大模型驱动的PubMed中文搜索引擎

马上搜索