Simulation of non-Newtonian blood flow in an end-to-side anastomosis.
In order to quantify the importance of non-Newtonian blood rheology on anastomotic flow patterns, the characteristics of Newtonian and non-Newtonian blood flows were compared in a 2-D, 45 degree end-to-side anastomosis model under both steady and unsteady flow conditions. All flows were assumed to be two-dimensional, and were simulated numerically using parameters consistent with blood flow in the femoral artery. A novel, purely viscous constitutive relation, based on a generalized form of the power law relation, was developed to model the non-Newtonian rheology of blood. The resulting wall shear stress patterns indicate that for the parameter values under consideration, non-Newtonian blood rheology has a significant effect on steady flow wall shear stresses, but no significant effect on unsteady flow wall shear stresses. Based on these and other simulations, a parameter is formulated that gives an indication of the importance of non-Newtonian blood rheology under a given set of flow conditions. In addition, an argument is presented for allowing the conclusions from this two-dimensional study to be extended to three-dimensional blood flow.
Ballyk
P D
PD
Department of Mechanical Engineering, University of Toronto, Ontario, Canada.
Steinman
D A
DA
Ethier
C R
CR
D000714:Anastomosis, Surgical; D001775:Blood Circulation; D018056:Hemorheology; D006801:Humans; D008954:Models, Biological; D014656:Vascular Surgical Procedures