Article

Mathematical modelling of pulsatile flow of Casson’s fluid in arterial stenosis

Department of Mathematics, Harcourt Butler Technological Institute, Kanpur 208 002, India; Department of Mathematics, K.N.I.T., Sultanpur, India
Applied Mathematics and Computation (Impact Factor: 1.35). 01/2009; DOI: 10.1016/j.amc.2007.05.070
Source: DBLP

ABSTRACT The effects of non-Newtonian nature of blood and pulsatility on flow through a stenosed artery have been investigated. It is of interest to note that the thickness of the viscous flow region changes with axial distance. An important result is that the mean and steady flow rates decrease as the yield stress increases. The critical value of the yield stress at which the flow rate behaviour changes from one type to another has been determined. Another important result of pulsatility is the mean resistance to flow is greater than its steady flow value, whereas the mean value of the wall shear for pulsatile blood flow is equal to steady wall shear stress. The velocity profiles and associated physiological characteristics involved in the analysis have been determined. Many standard results regarding Casson and Newtonian fluids flow, uniform and steady flow in an artery can be obtained in the present analysis as the special cases.

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