Comparative Study of Mixed Convection Effects on MHD Casson Dusty Two-Phase Flow over a Stretching Sheet

The present study investigates the nonlinear mixed convection flow and heat transfer characteristics of a magnetohydrodynamic (MHD) Casson dusty fluid over a stretching sheet in the presence of internal heat generation effects. The influences of space-dependent and temperature-dependent heat generation parameters are incorporated into the analysis. Using suitable similarity transformations, the governing nonlinear partial differential equations are converted into a system of ordinary differential equations and solved numerically using the Runge-Kutta-Fehlberg (RKF) method combined with the shooting technique. The analysis is performed for the parameter ranges M = 0-1,β = 0.5-1.5,Qt = 0-0.4,Qe = 0-0.4, with a comparative investigation between the absence (λ = 0) and presence (λ = 0.5) of mixed convection. The results show that increasing the Casson parameter significantly reduces the fluid velocity while enhancing the temperature distribution, whereas the magnetic parameter suppresses the momentum boundary layer because of the Lorentz force. Both space-dependent and temperature-dependent heat generation parameters increase the thermal boundary layer thickness. Furthermore, mixed convection enhances fluid motion and improves the local heat transfer rate compared with the λ = 0 case. The fluid-phase velocity and temperature are consistently higher than those of the dust phase over the entire parameter range considered. These findings provide useful insight into thermal transport and flow control in polymer extrusion, metallurgical processing, cooling of stretching surfaces, lubrication systems, and related heat-transfer devices.