An ideal surface, radiation model applied in many manufacturing and materials processing systems mast be able to take into account specular, spectral, and shadowing effects with complex geometries, and must be computationally efficient to permit its inclusion in the fluid flow a,td heat transfer models. in this study, a novel surface radiative heat transfer method is developed to meet ail these practical needs. The present model is based on the discrete transfer method (DTM). A direct application of the DTM to modeling surface radiative brat transfer may result in a large error due to strong ray effects. in order to eliminate these ray effects, rite DTM is modified by considering radiation contribution from all surface cells intercepted by a control angle. Calculation of these surface cell a, ens, represents one of the most important tasks in the modified DTM (MDTM), an it is described in detail in this study. To investigate the accuracy and efficiency of the MDTM, three benchmark problems covering different geometric and boundary conditions are considered, and the present solution is compared with the solutions from the exact approach the DTM, and discrete ordinates method (DOM). For each problem, the accuracy of the MDTM, DTM, and DOM appears to be affected by the angular discretization. For a reasonable fine angular discretization, the solutions from the MDTM and DOM match the exact solution very wed, while the solution from the DTM usually shows strong ray effects. The CPU times spent on rite MDTM and DTM ave very similar, hut they are usually orders of magnitude less than that for the DOM. The present study indicates that the MDTM is not only accurate bur also very efficient for modeling complicated surface radiation problems, Such a model will greatly benefit the simulation of many manufacturing and materials processing systems. [References: 8]
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