腹主动脉瘤几何形态对血液动力学影响的三维数值分析

Effect of geometry configuration of abdominal aortic aneurysm on hemodynamics by 3D numerical analysis

目的研究腹主动脉瘤不同形态学对瘤内血液动力学的影响,为临床预估动脉瘤的破裂提供参考。方法根据动脉瘤影像学上的特点建立不同几何形态的数学模型,采用计算流体动力学(CFD)方法,在周期性脉动速度入流、刚性壁面以及血液为牛顿流体的条件下,对一个心动周期内瘤内流场进行数值分析研究,比较不同几何形态腹主动脉瘤内血液动力学。结果非轴对称模型可造成相对较大的壁面剪应力;带有峰值偏移和曲率半径偏转的腹主动脉瘤,瘤内漩涡的发展变化会随着几何形态的不同而产生变化。结论腹主动脉瘤内流场特征的变化受到不同形态学的影响。

Objective The effect of different geometry configurations of abdominal aortic aneurysm on hemodynamics was investigated to supply some information for clinical diagnosis on aneurysm rupture, Methods Different models of the aneurysms were established using its Image data, The flow in the aneurysm was analysed by using the method of computational fluid dynamics under the condition of pulsatile input flow, rigid wall and Newtonian blood flow. The differences of these models were compared. Results The asymmetry model would cause larger value of wall shear stress comparably and have influence on the rupture of aneurysm, The vortexes in the models with excursion of peak value and in the deflected model were changed with different geometry configurations. Conclusion The different geometry configurations of AAA（abdominal aortic aneurysm） would affect the hemodynamics in the aneurysm.