Boundary element solver for coupled conduction-radiation heat transfer in nonhomogeneous media

In the present Paper, a boundary element solver is developed for the simulation of coupled conduction-radiation heat transfer in three-dimensional nonhomogeneous participating media. First, the boundary integral equations for radiation heat transfer in nonhomogeneous participating media are formulated. By using a simple variable transformation and with the aid of the Newton iterative scheme, the boundary integral equation for the nonlinear energy equation is obtained. For this strongly coupled system, a two-level iterative scheme is developed. Then, the boundary element method is adopted to discretize the resulting coupled system of integral equations. For the nonconvex geometries, a developed element-subdivision technique is adopted to handle with the visibility factor appearing in the radiative integral equations. Numerical examples show that the present algorithm is effective and efficient.