Abstract In most engineering applications, optimizing heat transfer is essential for improving the performance of systems such as heat exchangers, microchannels, and thermal storage units. Incorporating forced convection, nanofluids, magnetic fields, and flexible structures can significantly alter the thermal performance. The present study investigated the coupled magnetohydrodynamic and fluid structure interaction forced convection of nanofluid flow around a heated square obstacle immersed in a channel with two inclined flexible fins attached to the upper and lower horizontal walls. The working fluid is nanofluid composed of Fe 3 O 4 nanoparticles suspended in water. The primary objective is to examine how variations in magnetic field orientation combined with flexible fins can be utilized as active control mechanisms to regulate flow behaviour and thermal efficiency. Key parameters considered included the Reynolds number (Re = 20, 50, 100), magnetic field angle ( γ = 0°, 45°, 60°, 90°), Hartmann number (Ha = 0, 30, 60), and Cauchy number (Ca = 10 −2 , 10 −6 ), which collectively controlled the nanofluid flow, deformation of elastic fins, and heat transfer characteristics. The governing equations were solved using the finite element method in addition to the arbitrary Lagrangian–Eulerian (ALE) formulation in order to accurately capture the deformation of the flexible fins and their interaction with the fluid domain. Results showed that increasing Reynolds number combined with lower Cauchy number and Hartmann number values increased the average Nusselt number, indicating an enhancement in the heat transfer efficiency.
Azzi et al. (Sun,) studied this question.