Lattice Boltzmann modeling of buoyant convection in an enclosure with differentially heated porous cylinders

Abstract

This study employs the Lattice Boltzmann Method, utilizing the Darcy-Brinkmann-Forchheimer model, to investigate buoyancy-driven heat transfer within an enclosure featuring differentially heated porous cylinders. The enclosure comprises two isothermal cylinders (one hot and one cold) separated by a distance within a cooled enclosure. It comprehensively assesses the impact of Darcy numbers ranging from 10-6 to 10-2, Rayleigh numbers spanning from 104 to 106, and various cylinder orientations. Specifically, five distinct configurations are considered, including horizontal alignment of hot and cold cylinders (Case A), vertical alignment of hot and cold cylinders (Cases B & C), and diagonal alignment of hot and cold cylinders (Cases D & E). The key findings highlight that the highest heat dissipation occurs in proximity to the heated cylinder, with certain orientations consistently demonstrating superior heat dissipation. The study explores the heat and flow characteristics at different Rayleigh numbers, examining these through streamlines and isotherms. Also, the impact of cylinder permeability on heat transfer features is comprehensively analyzed and reported. The findings of this research offer valuable insights for optimizing the placement of electronic components within compact electronic cabinets, with potential benefits for electronic cooling and thermal management.