A numerical analysis of pulsatile flow in a wavy channel with periodically converging-diverging cross sections was performed by the finite element method. The present treatment was limited to the Stokes flow regime, and the effects of Womersley number and amplitude coefficient of flow rate oscillation on the flow behavior and wall vorticity were studied.
As the Womersley number increases, the flow pattern departs from the quasi-steady state. A circulation vortex occurs during the deceleration phase and the vortex behavior is dependent on both the Womersley number and the amplitude coefficient of flow rate oscillation. The dynamic response of the wall vorticity to the flow rate is dependent on the Womersley number only. The amplitude ratio and the phase difference vary sharply along the wavy wall, and these minimum and maximum values appear at the minimum cross section and near the maximum cross section of the channel, respectively.