Numerical results for radiative heat transfer in finite cylindrical medium with isotropic scattering

Abstract

In recent years, the interest in radiative heat transfer in cylindrical media has increased primarily because of its several applications related to combustion chambers, furnaces, and high temperature heat exchangers. Although there are many papers dealing with the radiative transfer in such geometry, there is lack of high precision benchmarks. Such scarcity is related to the fact that some researches present inaccurate results and most published works are limited to presenting results only in graphics. The shortage is more evident in the case of multidimensional problems, like those in which incident radiation and radiative heat fluxes vary in the axial direction. These problems can be approached in many ways; in the integral formulation, the angular variables are completely eliminated by integration over the solid angle, which allows the elimination of the ray effect and the consequent obtainment of more accurate numerical results. A strategy that can be used simultaneously with the integral formulation is the use of the singularity-subtraction technique with the Nyström method, which provides high quality numerical results with relatively low computational times if combined with mathematical refinements. Following this methodology, in the present research, radiative heat transfer problems in finite cylindrical media with isotropic scattering are solved. High precision numerical results for incident radiation and radiative heat fluxes in the radial and axial directions are provided and validated by comparing with results available in the literature.