Re-creating Hottel’s emissivity charts for carbon dioxide and extending them to pressure using HITEMP-2010 data base

The pioneering work of Hottel and co-workers produced emissivity charts for carbon dioxide, water vapor and their mixtures. Besides the work of Hottel, Leckner’s analytical expressions for predicting gas emissivities, published in 1972, are widely used. In this work we produce more accurate charts applicable to 1 bar pressure and produce graphs up to 40 bar . Both are based on the most recent HITEMP-2010 spectral data base. Our calculations provide CO 2 emissivity values that at atmospheric pressure differ by around 25% from Hottel’s data while at 40 bar pressure they differ by as much as 80%. The calculated total emissivities of carbon dioxide have been tabulated in EXCEL program (as Supplementary material) so as to facilitate very accurate interpolations without resorting to pressure corrections. We found impossible to develop pressure correction formulae which would be accurate over the 0.1– 40 bar pressure range.