Department of Mechanical Engineering, Indian Institute of Technology Patna, Bihta, Bihar 801103, India.
Department of Mechanical Engineering, Indian Institute of Technology, Kharagpur, Kharagpur, West Bengal 721302, India.
Math Biosci. 2018 Apr;298:1-18. doi: 10.1016/j.mbs.2018.01.008. Epub 2018 Feb 1.
The present work reports numerical simulations of blood flow patterns and wall shear stress (WSS) distributions in stenotic arteries, modelled as straight tubes. Inflow waveforms have been generated for different pulse rates considering constant volumetric flow during each pulsation cycle and a two-element windkessel model has been used to specify the outlet pressure. It is noticed that the non-Newtonian shear thinning rheology of blood produces more accurate and realistic predictions of the flow field as compared to the Newtonian assumption. Further, the effects of variation of pulse rates on the spatial and temporal distribution of WSS and oscillatory shear index (OSI) have also been studied for both axisymmetric and asymmetric stenosis. The changes in the mean flow features due to changes in pulsation frequencies have also been reported.
本工作报道了狭窄动脉中血流模式和壁面切应力(WSS)分布的数值模拟,这些狭窄动脉被建模为直管。考虑到每个脉动周期内的恒定体积流量,针对不同的脉搏率生成了入口流动波形,并使用双元素风箱模型来指定出口压力。人们注意到,与牛顿假设相比,血液的非牛顿剪切稀化流变学可以更准确和真实地预测流场。此外,还研究了脉动率变化对轴对称和非轴对称狭窄的 WSS 和振荡剪切指数(OSI)的时空分布的影响。还报告了由于脉动频率变化而导致的平均流动特征的变化。