Simulation of enhancement techniques impact on fluid dynamics and thermal mixing of laminar forced convection flow

Methods for enhancing fluid dynamics and thermal mixing in 3D open flow were performed and evaluated numerically in the current study. The impacts of a grouping of active and passive techniques of enhancement, namely: nonuniform magnetic field, complex geometry and nanofluids, on hydrodynamic and thermal behaviors were assessed. Flow characteristics such as degree of mixing, Nusselt number, and secondary flow structure indices were evaluated for various enhancement protocols being considered. An external magnetic field was applied in this project in two ways: over the entire channel or on specific stretches of the complex duct. In addition, mentioned flow features are examined along the channel with the number of Hartmann (Ha) ranging between 0 and 50 and three angles of orientation of the magnetic field (0, π /4 and π /2). The results show that the optimal protocol to achieve good thermal mixing between hot and cold fluids with a degree of mixing exceeds the 90% is for a nonuniform use of magnetic force oriented by π /2 or π /4. Moreover, it was observed that by applying the same optimized protocol, the parietal heat transfer represented by the Nusselt number was increased by more than 45%.