Heat transfer enhancement in lid-driven cavity with rotating cylinder: Exploring NEPCMs and magnetic field effects

Abstract

This numerical study investigates the influence of magnetic field orientation and Nano-Encapsulate Phase Change Materials (NEPCMs) on heat flow in mixed convection. The physical model consists of a cavity with a square lid and an isothermal rotating cylinder and Ga@SiO2 is selected as the NEPCM material. The numerical predictions are achieved by finite volume method. The governing equations are resolved employing the finite volume method. The credibility of the prevailing method is affirmed through a comparison of its predictions with findings from existing literature. The analysis focuses on assessing the effects of Richardson number (Ri), temperature of fusion position (θf), and magnetic field orientation angles (α). The findings reveal that optimal heat transfer occurs within the fusion position range of 0.3 to 0.6. Moreover, the incorporation of NEPCM results in a substantial increase in the Nusselt number by >20%. Although the magnetic field generally diminishes heat transfer, specific α and Ri ranges exhibit enhancements of up to 3.34%.