Calculations of non-gray gas radiative heat transfer by coupling the discrete ordinates method with the Leckner model in 3D rectangular enclosures

Abstract

In this study a new approach for radiation heat flux calculations by coupling the discrete ordinates method with the Leckner global model is introduced. The aim is to analyze the radiative heat transfer problem within a three-dimensional enclosure filled with non-gray gas mixture of \(\hbox {H}_{2}\hbox {O}\) and \(\hbox {C}\hbox {O}_{2}\). A computer code developed by this approach is applied to radiative calculations in three groups of well-known test cases published previously; considering homogeneous and inhomogeneous isothermal and non-isothermal participating media. All results are compared with well-known calculations based on statistical narrow band model. Also a new series of predictions for a medium with non-black walls and various mixture of \(\hbox {H}_{2}\hbox {O}\) and \(\hbox {C}\hbox {O}_{2}\) is performed to demonstrate the applicability of the Leckner model. The effect of different compositions of \(\hbox {H}_{2}\hbox {O}\) and \(\hbox {C}\hbox {O}_{2}\) on the radiative transfer within modern combustors is also examined. Based on the results obtained, it is believed that the discrete ordinates method coupled with the Leckner global model despite of its inherent simplicity and low computational cost is sufficiently accurate. For its convenient use, this method is suitable for a wide range of engineering calculations of participating media as well as for its link to previously written computational fluid dynamics codes.