Numerical solutions of non-gray gases and particles radiative transfer in three-dimensional combustion system using DRESOR and SNBCK

Abstract

The radiative intensity emitted by non-gray gases and particles can be captured by the charge-coupled device (CCD) camera with more than a thousand pixels in the combustion diagnostic. A solution to efficiently provide radiative intensity with high directional resolution in non-gray gases and particles medium is essential for the analysis of combustion system. In this paper, a three-dimensional enclosure filled with non-gray gases and particles was investigated and two real combustion cases were simulated to estimate the accuracy of the DRESOR method. The radiative heat flux, source term and radiative intensity with different directional resolutions were calculated by the DRESOR and DOM methods using SNBCK model. The results showed that the radiative heat flux and source were in good agreement with the reference results, and similar radiative intensities with low directional resolution were obtained by the DRESOR and DOM methods. For the non-isothermal case, the relative difference of maximum intensity between the results calculated with 288 and 13106 directions was 54.23% which was obviously larger than those in isothermal cases. A higher directional resolution was needed for the non-isothermal case. When the high directional resolution scheme was selected, the computational efficiency of the DREOSR method was significantly higher than that of the DOM method. The time consumed by the DOM method was about seven times of that consumed by the DRESOR method when the discrete directions were 800. The DRESOR method and SNBCK model which could obtain radiative intensity with high directional resolution efficiently for non-gray gases and particles medium, was more suitable for the analysis of three-dimensional combustion system.