Hydrothermal behavior and entropy analysis of double-diffusive nano-encapsulated phase change materials in a porous wavy H-shaped cavity with baffles: Effect of thermal parameters

The hydrothermal behavior and entropy analysis of the double-diffusive Nano-Encapsulated phase change materials (NEPCMs) is a hot topic which is applicable in new fields such as batteries, solar energy systems, and electronic devices. This study investigates the thermal behavior of the double-diffusive NEPCMs in a porous H-shaped wavy cavity with two baffles at the top rib. Introduction of Forchheimer-Brinkman expanded Darcy medium comprising of NEPCMs with base fluid in an H-shaped cavity with wavy-shaped walls is the novelty of the present study. The Forchheimer-Brinkman expanded Darcy theory is used to model the behavior of porous media in the cavity. The effect of various parameters such as Rayleigh number Ra (10⁴–10⁶), non-dimensional fusion temperature θ_f(0.1–0.3), buoyancy ratio N (1–3), Darcy number Da (10⁻¹–10⁻⁵), porosity parameter ε(0.3–0.7), and Lewis number Le (2–8) on the hydrothermal behaviors and the Nusselt and Sherwood numbers is considered. The Navier-Stokes equations are used as the governing equations by the consideration of the Buoyancy driven flow and using Finite Element Method (FEM) for discretization of the non-dimensional governing equations. The results reveal that Ra and N have a positive influence on convective heat and convective mass transfer. However, the Da and Le have a negative efficacy on Sh_avg and Nu_avg. Besides, the phase change area increases slightly by increasing Ra and buoyancy ratio. Moreover, the θ_f may have a positive influence on convective heat transfer and negative impact on convective mass transfer.