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Show __Ta 1 Radiative Heat Transfer Simulation of High Temperature Diffusion Combustion in a Furnace by Nongray Gas Model Yoshlkazu SUWA, Hiroshi OHTA, Masahisa SHINODA, Hideyuki AOKI and Takatoshi MIURA Department of Chemical Engineering, Tohoku University 07, Aoba, Aramaki, Aoba-ku, Sendai 980-8579 Japan Abstract Radiative heat transfer of the high temperature diffusion combustion in a furnace was analyzed by assuming the radiative properties of combustion gases that were nongray and inhomogeneous medium. The high temperature diffusion combustion has been utilized in industrial furnaces, and the prediction of heat transfer in the combustion furnaces is expected. Since the radiation occupies the heat transfer in high temperature gas, accurate estimations of gaseous radiative property, such as H20, C 0 2 and other species are required. It is necessary to discuss whether the application of nongray gas treatment to the numerical simulation of high temperature diffusion combustion leads to high performance prediction and shorter computational time than that of gray gas treatment or not. In this study, the discrete-ordinates method was used to solve the radiative transfer equation. The nongray gas approximation based on the exponential wide-band model was compared with the gray gas one in order to estimate the radiative properties of the combustion gases. 1 Introduction The combustion technology of the high temperature air combustion [1, 2] is realized by using 1000 °C or higher temperature preheated air. In industrial furnaces to which this technology is applied, it produces high thermal efficiency and low N O x and C 0 2 emissions. It is important to predict and understand the effect of the high |
