Cerebral aneurysm is a fatal neurovascular disorder. Computational fluid dynamics simulation of aneurysm haemodynamics is one of the most important research tools which provide increasing potential for clinical applications. However, computational fluid dynamics modelling of such delicate neurovascular disorder involves physical complexities that cannot be easily simplified. Recently, it was shown that the Newtonian simplification used to close the shear stress tensor of the Navier-Stokes equation is not sufficient to explore aneurysm haemodynamics. This article explores the differences between the latter simplification, non-Newtonian power-law model and a newly proposed quasi-mechanistic model. The modified Krieger model, which treats blood as a suspension of plasma and particles, was implemented in computational fluid dynamics context here for the first time and is made available to the readers in a C# code in the supplementary material of this article. Two middle-cerebral artery and two anterior-communicating artery aneurysms, all ruptured, were utilized here as case studies. It was shown that the modified Krieger model had higher sensitivity for wall shear stress calculations in comparison with the other two models. The modified Krieger model yielded lower wall shear stress values consistently in comparison with the other two models. Moreover, the modified Krieger model has generally predicted higher pressure in the aneurysm models. Based on published aneurysm rupture studies, it is believed that ruptured aneurysms are usually correlated with lower wall shear stress values than unruptured ones. Therefore, this work concludes that the modified Krieger model is a potential candidate for providing better clinical relevance to aneurysm computational fluid dynamics simulations.

中文翻译：

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使用牛顿，幂律和准机械血液粘度模型对脑动脉瘤进行计算流体动力学模拟。

脑动脉瘤是一种致命的神经血管疾病。动脉瘤血流动力学的计算流体动力学模拟是最重要的研究工具之一，为临床应用提供了越来越大的潜力。但是，这种微妙的神经血管疾病的计算流体动力学建模涉及物理复杂性，无法轻易简化。最近，研究表明，用于关闭Navier-Stokes方程的切应力张量的牛顿简化法不足以探索动脉瘤的血流动力学。本文探讨了后者的简化，非牛顿幂律模型与新提出的准力学模型之间的区别。修改后的Krieger模型将血液视为血浆和颗粒的悬浮液，本文首次在计算流体动力学上下文中实现，并通过本文补充材料中的C＃代码提供给读者。本文将两个均破裂的大脑中动脉和两个前交通动脉瘤作为案例研究。结果表明，与其他两个模型相比，改进的Krieger模型对壁面剪应力计算具有更高的灵敏度。与其他两个模型相比，修改后的Krieger模型始终产生较低的墙体剪应力值。此外，修改后的Krieger模型通常预测动脉瘤模型中的压力更高。基于已发表的动脉瘤破裂研究，据信破裂的动脉瘤通常与壁破裂应力值低于未破裂的动脉瘤有关。因此，