Abstract:This paper examines the thermal and solutal behaviour of three-dimensional MHD ferrofluidflow over a shrinking sheet, with relevance to magnetic cooling, micro-thermal devices, andadvanced heat-management systems. The model accounts for thermal radiation, viscousdissipation, and a non-uniform heat source/sink, all of which significantly influence thetransport characteristics of ferrofluids. By applying appropriate similarity transformations,the governing equations are reduced to a set of coupled nonlinear ODEs, which are thensolved numerically using the MATLAB bvp5c shooting method. An Engine Oil-basedferrofluid is selected due to its practical usefulness in cooling and heat-exchange applications.Graphical and tabulated results are presented to illustrate how various physical parametersaffect the velocity field, temperature distribution, skin-friction coefficient, and local Nusseltnumber. The study shows that an increase in nanoparticle volume fraction enhances thevelocity profiles, indicating improved momentum diffusion within the ferrofluid. Conversely,a higher Eckert number leads to reduced heat-transfer rates as a result of intensified viscousheating. The outcomes demonstrate the potential of ferrofluid-based MHD flows forimproving the efficiency of thermal-control and magnetic cooling technologies.