Numerical Studies on Physiological Pulsatile Flow Through Stenotic Tubes

Abstract

Numerical studies have been carried out for laminar physiological pulsatile flow through a circular tube with smooth single and double constrictions. A second-order finite volume method based on the modified SIMPLE method with collocated non-orthogonal grid arrangement has been developed. For a vessel with single constriction, the characteristics of the incoming pulsation waveform of the flow rate have a considerable impact on the flow behaviour in the tube in terms of streamline, dimensionless pressure and wall vorticity distributions. The variation of the geometry of the stenosis also influences the interior flow pattern although the incoming flow remains consistent. The extent to which the different parameters affect the vortical flow is not the same for systolic and diastolic phase of the physiological pulsation. For double constriction, the post-stenotic flow behaviour downstream the second stenosis is not as severely affected by the incoming flow as for single constricted tubes. Distinct geometric configurations of the two stenoses will result in obvious variations of the induced vortices.