| Abstract: | The effects of pulsatile amplitude on sinusoidal laminar flows through a rigid pipe with sharp-edged ring-type constrictions have been studied numerically. The parameters considered are: mean Reynolds number (Re) of the order of 100; Strouhal number (St) in the range 0·0–3·98; Womersley number (Nw) in the range 0·0–50·0. The pulsatile amplitude (A) varies in the range 0·0–2·0. The flow characteristics were studied through the pulsatile contours of streamline, vorticity, shear stress and isobars. Within a pulsatile cycle the relations between instantaneous flow rate (Q) and instantaneous pressure gradient (dp/dz) are observed to be elliptic. The relations between instantaneous flow rate (Q) and pressure loss (Ploss) are quadratic. Linear relations exist between instantaneous flow rate (Q) and maximum velocity, maximum vorticity and maximum shear stress. © by 1997 John Wiley & Sons, Ltd. |
