Simulation of natural convection in eccentric annulus: A combined Lattice Boltzmann and Smoothed profile approach

In this paper a combination of lattice Boltzmann method and smoothed profile method is applied to simulate natural convection heat transfer in horizontal eccentric annuals. In this approach, the fluid-solid interface has a thickness which is comparable to grid spacing and it varies continuously from zero in fluid region to one in solid region. A two dimensional double distribution function lattice Boltzmann method is employed to simulate fluid flow and temperature profiles simultaneously. In order to implement the velocity and temperature boundary conditions, the force term and heat source/sink are included in the evolution equations. Since SPM employs fixed Eulerian nodes to implement all calculations, the computational efficiency is improved greatly. The influence of vertical, horizontal and diagonal eccentricities at various positions is investigated. Isotherms, Streamlines and Nusselt numbers are given for each case.