Immersed boundary-lattice Boltzmann simulation of natural convection in a square enclosure with a cylinder covered by porous layer

摘要

Numerical simulations are performed for natural convection in a square enclosure with a cylinder covered by a porous layer. The Darcy-Brinkmann-Forchheimer equation is adopted to describe the flow in both fluid and porous regions. To avoid the treatment of complicated interface conditions, the single domain approach based on lattice Boltzmann method (LBM) is used to solve the unified governing equation. The curved velocity and thermal boundary conditions are treated by immersed boundary method (IBM). The effects of several physical parameters, including thermal conductivity ratio, Rayleigh number and Darcy number on flow and heat transfer characteristics are investigated. The numerical results indicate the addition of a porous layer can change the flow pattern and enhance the heat transfer.