An alternative discrete ordinates method with interpolation and source differencing for two-dimensional radiative transfer problems

Abstract

A new discrete ordinates interpolation method for numerical solution of the radiative transfer equation in two-dimensional enclosures with participating media is proposed and examined. This method can be applied to any nonorthogonal grids commonly employed in analyzing fluid flow and heat transfer. Numerical accuracy and false scattering of the current interpolation method are investigated and compared with those of the conventional scheme of the discrete ordinates method (CDOM) and Raithby's finite-volume method (FVM). The discrete ordinates interpolation method is found to be more accurate and to produce less false scattering than the CDOM with a diamond scheme and the FVM from a preliminary test. Two sample problems, a square cylinder with uniform heat source with or without scattering and a quadrilateral cylinder with constant gas temperature, are considered to further test and explore the validity of the new scheme. The results of the new method have shown good accuracy and versatile applicability for the prediction of radiative heat transfer.