Effect of Taper Angle on Wall Shear Stress in Tapered Right-Angle Branch during Laminar Steady Flow

The present paper describes the experimental work on the flow through the tapered branch model with the taper angle of 1°, in which a tapered side branch bifurcates at a right angle from a tapered trunk. The results show that in steady flow the wall shear stress reaches a maximum at the upstream corner of the side branch and varies significantly with position along the proximal wall in the form of a damped sine wave. The variation is closely associated with the secondary flow from the trunk to the side branch. Furthermore, the wall shear stress in the tapered branch varies more moderately than that in the parallel straight branch, and the occurrence of separation flow would be suppressed around the branch point. Therefore, the results of the present study suggest that the tapered branch is more suitable for a human artery than the parallel straight branch.