Three-dimensional thermal analysis of radiative viscoplastic fluid flow stirring by anchor impeller within a stirred tank

The agitation of viscoplastic fluids (e.g., polymer melts, drilling muds) in stirred tanks remains a critical challenge due to their yield-stress behavior and poor heat transfer efficiency. The objective of this research is to study a three-dimensional (3D) numerical simulation, focused on the analysis of the thermal approach of viscoplastic fluid (Bingham-Papanastasiou model) inside an agitated vessel, equipped with an Anchor impeller agitator. The sidewall of the vessel is assumed to be at a hot temperature T_h, whereas the working fluid has an initial cold temperature T_c. The study focuses on the impact of inertia parameters for a range of inertia values of Reynolds number (Re = 1, 10, 100, 200) on the global characteristics of the stirred system (heat transfer rate, hydrodynamic flow pattern, and energy consumed inside the agitation process). The numerical results show the dominance of tangential flow inside the stirred vessel with (Re = 1, 10), whereas, with the highest inertia value (Re = 100, 200), a secondary axial flow appears, which leads to amelioration in the hydrodynamic behavior along the agitated vessel. In addition, the enhancement of thermal behavior by amplifying the Nusselt number (Nu), especially with a Reynolds number value of Re = 200, where Nu increases by 35.27 % with a reduction of energy consumption of 98.81 %.