Affiliations: Department of Mechanical Engineering, 5 King’s College Road, University of Toronto, Toronto, Ontario M5S 1A4, Canada
Abstract: 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° 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.
Keywords: Blood, end-to-side anastomosis, non-Newtonian, generalized power law model, numerical simulation, finite elements
DOI: 10.3233/BIR-1994-31505
Journal: Biorheology, vol. 31, no. 5, pp. 565-586, 1994
