Numerical analysis of magnetohydrodynamic (MHD) convection using CNT-based nanofluids in a wavy-shaped enclosure with a double lid

Abstract

In the present study, numerical investigations are conducted to examine the thermal performance of the magnetohydrodynamic mixed convection flow in a double lid-driven wavy walls square cavity, filled with CNTs. The cavity consists of two undulating lateral walls oriented toward each other, accompanied by horizontal cold walls positioned at the upper and lower ends, exhibiting opposing motion. Governing equations based on the Boussinesq approximation are solved using the CFD analysis. Reynolds numbers, Richardson numbers, Prandtl numbers, Hartmann numbers, nanoparticle volume fractions, wavy walls wave numbers, and amplitudes of waviness affect Nusselt number. The inquiry examines streamlines, isotherms, and Nusselt numbers. Convective current in the hollow enclosure diminishes as Hartmann number increases according to magnetic field strength. Wave number 20 and amplitude 0.1 result in a greater Nu value. Nanoparticles in the primary fluid, at low volume concentrations, quadruple the baseline Nusselt number. SWCNTs (single-walled carbon nanotubes in water) have a high Nusselt number in the heated, wavy-walled enclosure, even under magnetic fields. The investigation reveals a maximum Nusselt number of 91.48 for a volume fraction of 0.1%, three times the previous notable data. This study analyzes how wavy walls, tilted magnetic fields, and CNT-based nanofluids increase enclosures Nusselt number.