Coupled radiation and mixed convection in an eccentric annulus using the hybrid strategy of lattice Boltzmann-Meshless Method

A numerical investigation has been made of the interaction of thermal radiation with laminar mixed convection in an eccentric annulus filled with participating media. As a hybrid approach based on a common multiscale Boltzmann-type model, the combination of lattice Boltzmann and direct collocation meshless methods (LB-DCM) is developed to solve the coupled problem of radiation and convection. Numerical simulations are conducted for different eccentricities, Rayleigh number, Reynolds number, convection-radiation parameter, and optical thickness. Results show that the LB-DCM combination is stable and accurate. In addition, this hybrid approach is easy to implement and has excellent flexibility in dealing with irregular geometries.