An efficient smoothed profile-lattice Boltzmann method for the simulation of forced and natural convection flows in complex geometries

In the present study, a numerical method based on the lattice Boltzmann method and smoothed profile method is proposed to simulate the forced and natural convection flows in complex geometries. The solid–fluid boundaries are replaced by a smoothed continuous interface with a finite thickness. A concentration function is used to identify the fluid and solid regions. The flow and temperature fields in different regions are solved on fixed grids. The force term and heat source/sink are added in evolution equations to impose the velocity and temperature boundary conditions. The present approach is validated by some thermal flows examples: flow around a heated circular cylinder, natural convection in a square cavity with a heated circular cylinder, natural convection in a concentric annulus. The computed results show good agreement with the previous data. The high efficiency of the present method is also verified.