A numerical analysis of pulsatile flow in a wavy channel with periodically converging-diverging cross sections was carried out by the finite element method. The variations of streamline and wall shear stress with Womersley number A^*, Reynolds number Re and oscillatory fraction of the flow rate P were studied.
A recirculation vortex occurs within the furrow of the wall during the acceleration phase for inertia-dominated flow but during the deceleration phase for viscosity-dominated flow. Its boundary is determined in terms of A*²/Re. As Re or P increases, higher modes appear in the time variation of wall shear stress owing to the non-linear effects, and also a kind of Reynolds stress occurs in the time-averaged wall shear stress.
An experimental flow visualization study additionally performed shows good agreement with the numerical analysis.