A Modified Exponential Wide Band Model for Gas Emissivity Prediction in Pressurized Combustion and Gasification Processes

Accurate and fast prediction of the gas emissivity in a wide range of pressure and temperature is very essential for i the accurate and efficient simulation of the combustion and gasification processes. In this work, the total emissivities of the main radiant species including H2O, CO2, CO, and their mixtures are first generated with the line-by-line (LBL) model and the HITEMP-2010 spectroscopic database at different total pressures varying from 0.1 atm to 30 atm and at different temperatures varying from 300 K to 2500 K. Then, the exponential wide band model (EWBM) is modified according to the LBL results and simplified using the polynomial fitting method and the table look-up scheme. Finally, a modified EWBM (M-EWBM) is presented. The performances of the EWBM, the M-EWBM, and the LBL model are comprehensively compared, and it is found that the M-EWBM is more accurate than the EWBM and can be as efficient as the weighted-sum-of-gray-gas model, making it very promising for the total gas emissivity prediction in the pressurized combustion and gasification simulations.