Comparison of Radiation Element Method and Discrete Ordinates Interpolation Method Applied to Three-Dimensional Radiative Heat Transfer(<Special Issue>Advanced Fluid Information)

This paper compares and scrutinizes the characteristics of radiation element method by ray emission model (REM^2) and discrete ordinates interpolation method (DOIM). A three-dimensional radiative heat transfer problem is solved within a rectangular enclosure containing absorbing, emitting, nonscattering medium with temperatures given as a sine function. The calculation results are validated with the zonal results and the analytical solution. Generally, the calculation results agree well with the exact solution. However, when the optically thickness is much larger than unity, the zonal and REM^2 results overestimate the heat source strength and wall heat flux, and when it is small, DOIM results underestimate them. The reasons and remedies are carefully discussed.