Effect of Hypertension and Hyperlipidemia on LDL Transport in Arterial Layers for Newtonian and non-Newtonian Aspects of Blood
Somnath Santra, Dipak Kumar Mandal and Somnath Chakrabarti
In the present numerical study, a mathematical model for the convective and diffusive transport of LDL in various layers of the arterial wall has been depicted. The transport in the lumen, endothelium, intima, internal elastic lamina and media of a straight axisymmetric arterial segment has been considered in the present analysis. The endothelium, intima, internal elastic lamina (iel) and media have been considered as a homogeneous porous layer. Navier-stokes equation and Darcy’s equation have been used for implementing the fluid flow in the lumen and the arterial wall respectively. The mass transport in the lumen has been modeled through the convection–diffusion equation; whereas volume averaged convection–diffusion–reaction equation has been used for simulating the mass transport through porous layers. This paper highlights the effect of hypertension and hyperlipidemia on LDL transport in arterial wall considering both the Newtonian and non-Newtonian characteristics of blood. The results have shown that the non-Newtonian property enhances species concentration in different arterial wall layers for both the cases. From the results, it is noted that the increment of LDL concentration is 2.98% more in intima layer for non-Newtonian model than Newtonian model under hypertension condition. Furthermore, the results also illustrate that LDL concentration increment is 5% higher in intima layer for non-Newtonian model than Newtonian model under hyperlipidemia condition.
Keywords: Newtonian model, non-Newtonian model, hypertension, hyperlipidemia, radial filtration velocity, atherosclerosis