Solution of radiative-convective heat transfer in irregular geometries using hybrid lattice Boltzmann-finite volume and immersed boundary method

Immersed boundary method (IBM) is introduced for solving the radiative transfer equation (RTE) to simulate the radiation heat transfer with natural convection in irregular geometries. IBM is organized based on the direct forcing method and sharp interface scheme. The Lattice Boltzmann method (LBM) with double multiple relaxation-time (MRT)-D2Q9 is adopted in computing the momentum and energy equations, and the finite volume method (FVM) is applied in the numerical solution of RTE with a pseudo-time-stepping approach. The FVM-LBM code is tested in benchmark geometries in two cases. The ability and performance of IBM are examined in an irregular geometry for Rayleigh number, Planck number, and optical thickness on thermal and flow fields. Static and Hopf bifurcation as an attractive effect of radiation heat transfer is noted. The significant benefit of IBM is using a unique mesh in simulating these problems.