MHD micropolar hybrid nanofluid flow through an annulus with discrete surface heaters: A study for optimal heat convection

Abstract

AbstractIn this study, natural convection through a micropolar hybrid nanofluid in a complex annulus, influenced by a static magnetic field and discrete heaters on the boundaries of the annulus has been investigated numerically. The annulus is formed using an elliptical cylinder enclosed by a square cylinder. Numerical simulations were performed to assess the optimal heat convection in six different configurations due to discrete/continuous heaters on the boundary of the annulus. The nonlinear coupled partial differential equations of motion and energy are solved with the finite difference method coupled with successive over relaxation and successive under relaxation. The effects of pertinent physical parameters on the flow and heat transfer were computed for the ranges of , , , and . Their effects are demonstrated using streamline and isotherms profiles. The average Nusselt number at the heating locations of the annulus boundaries was computed to categorize the configuration for optimal heat convection. The results of this study reveal that when the inner elliptical cylinder is subjected to discrete heaters and the square enclosure has a continuous heater, the optimal convection of heat is from the inner cylinder. Furthermore, the convective heat transfer combined with the heaters on the inner and outer boundaries of the annulus was maximum for the configuration in which the inner elliptical cylinder is subjected to discrete heaters and centrally placed discrete heaters on the sides of the square enclosure.