MHD hybrid nanofluid convection and phase change process in an L-shaped vented cavity equipped with an inner rotating cylinder and PCM-packed bed system

Abstract

In this study, convective heat transfer and phase change process are analyzed for an L-shaped vented cavity equipped with an inner rotating cylinder and phase change material-packed bed (PCM-PB) system under magnetic field during hybrid nanofluid convection. The numerical work is performed for different values of Reynolds number (Re between 200–1000), rotational Reynolds number (Rew between −1000–1000), size of the cylinder (R between 0.05H-0.15H) and Hartmann number (Ha between 0–40) while hybrid Ag/MgO nanoparticle loading amount in water is 2%. It is observed that the vortex size and their distributions in the cavity and within the PCM-PB system can be controlled by varying rotating cylinder size and rotational speed along with the magnetic field. With higher cylinder size, phase change becomes fast while complete phase transition time (tP) is reduced by about 22% and average Nusselt number (Nu) rises by about 86% at Rew = −1000. Rotational direction of the cylinder is effective for phase transition dynamics while at Rew = −1000, tP rises up to 27% when compared to non-rotating cylinder case. Magnetic field strength is a good parameter for vortex suppression. At the highest strength, phase change becomes fast and average Nu rises up to 26.5% at Rew = −1000. ANFIS based modeling approach is used for impacts of rotating cylinder on the phase change dynamics in the L-shaped vented cavity.