Mathematical Modelling of the Effects of Trans Fat on Bioheat Transfer and Magnetohydrodynamic Blood Flow through a Constricted Channel Using the Oscillatory Perturbation Method

Abstract

This study develops a mathematical model for investigating the effects of trans-fat-related atherogenic lipid burden on blood flow, heat transfer, and concentration transport through a constricted artery under magnetohydrodynamic conditions. The artery is represented as a constricted channel containing a porous region, while blood is treated as an incompressible, electrically conducting fluid subjected to pulsatile pressure forcing and a transverse magnetic field. The governing momentum, energy, and concentration equations incorporate porous resistance, magnetic interaction, bioheat transfer, mass diffusion, concentration reaction, and concentration-induced buoyancy. The resulting coupled equations are treated using the Oscillatory Perturbation Method, and the effects of the governing parameters are examined through velocity, temperature, concentration, and arterial-constriction contour plots. The results show that variations in Darcy number from 0.01 to 0.05 significantly modify porous resistance and consequently influence blood velocity. Increasing the stenosis parameter from 0 to 0.55 produces progressively stronger arterial geometrical deformation, while increasing the magnetic parameter from 0.5 to 3 strengthens magnetic resistance and suppresses blood motion. An increase in the pressure-gradient parameter from 1 to 4 enhances the driving force and increases the magnitude of the velocity response. Concentration-related parameters substantially influence mass transport and its coupling with momentum, with concentration reaction values from 0.2 to 2 affecting concentration attenuation and concentration buoyancy values from 0 to 15 modifying concentration-momentum interaction. Increasing the Prandtl number from 21 to 25 alters the thermal field, whereas increasing the Schmidt number from 0.2 to 1.0 restricts concentration diffusion within the arterial region. The constriction results further demonstrate the strong influence of arterial geometry on the available flow passage and the resulting haemodynamic environment. Medically, the findings suggest that arterial deformation, porous resistance, altered lipid-related transport, and pressure forcing can interact to produce significant changes in blood-flow and transport characteristics within a stenosed artery. The concentration variable is interpreted as an effective trans-fat-related atherogenic lipid burden rather than direct deposition of intact dietary trans-fat particles. The model therefore provides a theoretical study for understanding coupled haemodynamic, thermal, and concentration-transport processes associated with atherosclerotic arterial constriction and provides a basis for future patient-specific and experimentally validated investigations.