Two -fluid nonlinear mathematical model for pulsatile blood D. S. Sankar
The Journal of Mechanical Science and Technology, vol. 23, no. 6, pp.1650-1669, 2009
Abstract : The pulsatile flow of blood through a catheterized artery is analyzed, assuming the blood as a two-fluid model with
the suspension of all the erythrocytes in the core region as a Herschel-Bulkley fluid and the peripheral region of plasma
as a Newtonian fluid. The resulting system of the nonlinear implicit system of partial differential equations is solved by
perturbation method. The expressions for shear stress, velocity, flow rate, wall shear stress and longitudinal impedance
are obtained. The variations of these flow quantities with yield stress, catheter radius ratio, amplitude, pulsatile Reynolds
number ratio and peripheral layer thickness are discussed. The velocity and flow rate are observed to decrease,
and the wall shear stress and resistance to flow increase when the yield stress increases. The plug flow velocity and
flow rate decrease, and the longitudinal impedance increases when the catheter radius ratio increases. The velocity and
flow rate increase while the wall shear stress and longitudinal impedance decrease with the increase of the peripheral
layer thickness. The estimates of the increase in the longitudinal impedance are significantly lower for the present twofluid
model than those of the single-fluid model.
Keyword :
Two-fluid model; Herschel-bulkley fluid; Newtonian fluid; Pulsatile flow; Catheterized artery; Longitudinal impedance
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