弯曲颈总动脉内流场的模拟实验研究

目的模拟研究弯曲颈总动脉定常流动速度剖面的不对称性。方法用粒子图像测速技术(PIV)测量并分析曲率分别为1:60和1:20的90°弯管模型在颈总动脉生理平均雷诺数、峰值雷诺数和极限雷诺数条件下,在不同位置的弯曲平面及其垂直方向的轴向速度剖面。结果当颈总动脉的曲率等于1:60时,在人生理平均流动雷诺数条件下,颈总动脉的速度剖面可用偏斜的抛物面来近似;当颈总动脉曲率增大或流动雷诺数增大时,弯曲平面上的速度剖面中部出现下凹趋势,垂直方向上出现M型速度剖面;沿管轴不同位置上的速度剖面形状不同。结论为确定颈动脉分叉定常流动不对称入口速度剖面条件,认识速度剖面的形状如何随流动雷诺数、弯管曲率和截面位置变化提供实验依据。

Experimental investigation of flow fields in the curved common carotid artery in vitro

Objective To study the asymmetry of velocity profile under steady flow condition in the curved common carotid artery(CCA) in vitro.Methods The PIV is used to measure velocity profiles on vertical and horizontal planes of CCA in different localities under physiological average,peak and limited Reynolds numbers of CCA models of 1:20 and 1:60 curvatures.Result The skewed parabolic profile is observed in CCA under 1:60 curvature and physiological average Reynolds number.As curvature and Reynolds number increase,the middle of horizontal profile appears sunken and the vertical profile is M-shaped.There are different profile shapes in different localities along the curved pipe.Conclusion The experimental data were provided for the asymmetric inlet velocity profile condition of carotid bifurcation,and for understanding the changes of velocity profiles shapes along with Reynolds numbers,curvature and localities of the curved pipe.