Interaction of mixed convection with non-gray gas radiation in a partially heated horizontal pipe: entropy generation analysis

Abstract

PurposeThis paper aims to numerically analyze the effect of non-gray gas radiation on mixed convection in a horizontal circular duct with isothermal partial heating from the sidewall. The influence of heater location on heat transfer, fluid flow and entropy generation is given and discussed in this study.Design/methodology/approachThe numerical computation of heat transfer and fluid flow has been developed by the commercial finite element software COMSOL Multiphysics. Radiation code is developed based on the T10 Ray-Tracing method, and the radiative properties of the medium are computed based on the statistical narrow band correlated-k model.FindingsThe obtained results depicted that the radiation considerably contributes to the temperature homogenization of the gas. The findings highlight the impact of the heater location on swirling flow. It is also shown that the laterally heating process provides better energy efficiency than heating from the top of the enclosure.Originality/valueThis study is performed to improve heat transfer and to minimize entropy generation. Therefore, it is conceivable to improve the model design of industrial applications.