Nanof luid Heat Transfer in Irregular 3D Surfaces under Magnetohydrodynamics and Multi-Slip Effects

This study employs the Buongiorno model to explore nanoparticle migration in a mixed convection second-grade f luid over a slendering (variable thickness) stretching sheet. The convective boundary conditions are applied to the surface. In addition, the analysis has been carried out in the presence of Joule heating, slips effects, thermal radiation, heat generation and magnetohydrodynamic. This study aimed to understand the complex dynamics of these nanof luids under various external inf luences. The governing model has been developed using the f low assumptions such as boundary layer approximations in terms of partial differential equations. Governing partial differential equations are first reduced into ordinary differential equations and then numerically solved using the Runge-Kutta-Fehlberg method (RK4) in conjunction with a shooting scheme. Our results indicate significant increases in Nusselt and Sherwood numbers by up to 14.6% and 23.2%, respectively, primarily due to increases in the Brownian motion parameter and thermophoresis parameter. Additionally, increases in the magnetic field parameter led to a decrease in skin friction coefficients by 37.5%. These results provide critical insights into optimizing industrial processes such as chemical production, automotive cooling systems, and energy generation, where efficient heat and mass transfer are crucial. Buongiorno model; velocity-slip effects; Joule heating; convective boundary conditions; Runge-Kutta-Fehlberg method (RK4).