MHD stagnation-point flow of a micropolar fluid with variable properties and slip over a stretching/shrinking sheet

This study examines the magnetohydrodynamic (MHD) stagnation-point flow of a micropolar fluid over a stretching/shrinking sheet, incorporating temperature-dependent viscosity and thermal conductivity under first-order slip conditions. The governing equations are transformed using similarity variables and solved analytically using the homotopy analysis method (HAM). The analysis shows that the slip parameter significantly enhances both velocity and microrotation near the wall (≈10–20%) by reducing surface resistance. In contrast, the magnetic parameter suppresses fluid motion, leading to a reduction in velocity and microrotation (≈2–3%) due to the opposing Lorentz force. Increasing the micropolar parameter decreases velocity while modifying microrotation, highlighting the strong coupling between linear and angular momentum transfer. Temperature-dependent viscosity reduces velocity (by 15–18%) due to increased internal friction, whereas variable thermal conductivity alters the temperature field and affects heat transfer. Additionally, higher Prandtl numbers decrease the thermal boundary layer thickness, thereby enhancing heat transfer rates. The results are in good agreement with existing studies, confirming the validity of the approach. This work provides useful insights for applications in microfluidics, polymer processing, and thermal management systems.