Effects of Reynolds number on physiological-type pulsatile flows in a pipe with ring-type constrictions

✍ Scribed by T.S. Lee; Z.D. Shi

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 297 KB
• Volume: 30
• Category: Article
• ISSN: 0271-2091
• DOI: 10.1002/(sici)1097-0363(19990730)30:6<743::aid-fld862>3.0.co;2-e

✦ Synopsis

The effects of Reynolds number on the physiological-type of laminar pulsatile flow fields within the vicinity of mechanical ring-type constriction in small pipes were studied numerically. The parameters considered are: the Reynolds number (Re) in the range of 50 -1500; Strouhal number (St) in the range of 0.00156-3.98; Womersley number (Nw) from 0.0 to 50.0. The pulsatile flows considered were physiological-type of simulated flows. Within a pulsating cycle, detailed flow characteristics were studied through the pulsating contours of streamline (), vorticity (V), shear stress (~) and isobar. The relations between the instantaneous flow rate (Q) and instantaneous pressure gradients (dp/dz) are observed to be elliptic. The relations between the instantaneous flow rate (Q) and pressure loss (P loss ) are quadratic. Linear relations were observed between the instantaneous flow rate (Q) and the maximum velocity, maximum vorticity and maximum shear stress. The Reynolds number of the flow in a pulsating cycle was found to have significant effects on the recirculation length and the pressure gradient within the pulsatile flow regime.