Magnetically Controlled Mixed Convection Nanofluid Flow With Slip and Suction: Implications for Thermal System Design

Abstract

This study numerically investigates mixed convective magnetohydrodynamic nanofluid flow over a nonlinearly stretching sheet with wall suction, velocity slip, and thermal slip. Particular emphasis is placed on the microscopic nanoparticle transport mechanisms of Brownian motion and thermophoresis and their coupling with macroscopic heat and mass transport. The governing partial differential equations, incorporating magnetic, buoyancy, thermal-radiation, and viscous-dissipation effects, are reduced to a coupled system of nonlinear ordinary differential equations via similarity transformations and solved numerically using MATLAB's bvp4c boundary-value solver. The principal novelty lies in the simultaneous treatment of magnetic field, mixed convection, thermal radiation, viscous dissipation, Lewis number, and combined velocity/thermal slip together with suction in a single nonlinearly stretching-sheet configuration, and in the physical interpretation of how these mechanisms jointly govern the momentum, thermal, and concentration boundary layers. Results show that an increasing magnetic field suppresses the Lorentz-force-retarded velocity field while increasing temperature and concentration through reduced convective cooling; enhanced mixed convection accelerates the flow, thinning the thermal and concentration boundary layers; thermal radiation and viscous dissipation raise the temperature profile; thermal slip lowers the temperature profile, while velocity slip and suction respectively increase and uniformly reduce the velocity, temperature, and concentration fields. Brownian motion and thermophoresis are shown to influence the temperature and concentration fields in contrasting ways. These findings offer quantitative guidance for selecting magnetic field strength, slip conditions, and suction rates in the design of nanofluid-based cooling and heating systems.