A Compressible Approach to Solve Combined Natural Convection-Radiation Heat Transfer in Participating Media

Abstract

The need for accurate prediction of combined natural convection-radiation heat transfer in participating media has resulted in developing a few different numerical methods with different capabilities. One important aspect in treating high-thermobuoyant flow fields is to impose the compressibility effects in predictions. The Literature shows that most previous research has used incompressible algorithms to solve the combined natural convection-radiation problem. However, the research in pure natural-convection heat transfer problems has shown that the Boussinesq assumption will not result in solutions with sufficient accuracies in domains with high temperature variations. In this work, we develop a hybrid incompressible-compressible method to solve the combined natural convection-radiation heat transfer in a participating medium without addressing the Boussinesq approximation. Our results show that there are significant differences between the compressible and incompressible results in treating such high-thermobuoyant flow fields. We also show that the compressibility effects become more dominant in combined natural convection-radiation problems than in the pure natural-convection problem. So, we conclude that use of the Boussinesq assumption cannot be definitely recommended in treating thermobuoyant flow fields with strong to moderate temperature gradients. Indeed, the current developed algorithm can be used to avoid the inaccuracies resulting from the incompressible treatment of such flow fields.

Notes

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