Transverse magnetic field with Hartmann number 5 reduced centerline velocity by approximately 60% and wall shear stress by up to 40% in pulsatile non-Newtonian blood flow in stenosed arteries.
Does a transverse magnetic field alter velocity distribution and wall shear stress in a mathematical model of pulsatile non-Newtonian blood flow?
A transverse magnetic field significantly alters pulsatile non-Newtonian blood flow by reducing centerline velocity and wall shear stress, providing theoretical insights for MRI safety and magnetic drug targeting.
Effect estimate: ~60% reduction in centerline velocity at Hartmann number 5 versus 0
Blood flow in human arteries is inherently pulsatile and exhibits non-Newtonian behavior, driven by the rhythmic cardiac cycle and influenced by shear-dependent viscosity arising from plasma and cellular interactions. This study investigates the magnetohydrodynamic (MHD) effects of a transverse magnetic field on pulsatile non-Newtonian blood flow, with particular emphasis on velocity distribution, wall shear stress (WSS), flow resistance, and hemodynamic responses in stenosed arteries. Blood is modeled as a Casson fluid, capturing shear-thinning and yield stress characteristics, while the transverse magnetic field generates a Lorentz force opposing flow. Governing momentum equations are formulated in cylindrical coordinates and solved using analytical techniques (Finite Hankel transforms) complemented by numerical simulations for pathological and pulsatile conditions. The analysis reveals that increasing the Hartmann number (Ha) significantly reduces centerline velocity, flattens velocity profiles, and decreases WSS, whereas higher Casson parameters (β) produce blunter, plug-like profiles with higher central velocity and lower boundary shear. Pulsatility, represented by the Womersley number (α), introduces phase-lagged oscillations, and stenosis severity amplifies local velocities and WSS, increasing flow resistance. Additionally, Joule heating due to induced currents modestly raises blood temperature, relevant for hyperthermia therapy. These findings have significant implications for MRI safety, magnetic drug targeting, and vascular disease management, providing quantitative insight into the interplay of magnetic fields, non-Newtonian rheology, and pulsatile hemodynamics in arteries.
Singh et al. (Thu,) conducted a other in Human arterial blood flow exhibiting pulsatile non-Newtonian behavior under pathological conditions including stenosis. Transverse magnetic field vs. No magnetic field (Hartmann number = 0) was evaluated on Hemodynamic changes including centerline velocity, wall shear stress, and flow resistance under application of transverse magnetic field (~60% reduction in centerline velocity at Hartmann number 5 versus 0). Transverse magnetic field with Hartmann number 5 reduced centerline velocity by approximately 60% and wall shear stress by up to 40% in pulsatile non-Newtonian blood flow in stenosed arteries.