Quantifying the Effects of Combustion Gases’ Radiation on Surface Temperature Measurements Using Two-Color Pyrometry

Abstract

This article developed an analytical two-color thermometry model combined with a mathematical radiative heat transfer model. The proposed model was used to investigate the performance of two-color pyrometry affected by absorption bands in hot combustion gases. This model was validated by comparing with a range of measured data and the results of other numerical solutions. The analysis of the temperature errors produced by a high-temperature H2O–CO2–N2 mixture in three measurement situations was presented. The presence of the high-temperature H2O–CO2–N2 mixture greatly affected the measurement accuracy of two-color pyrometry. Minimizing the absorption and emission effects by selection of the instrument spectral band is useful when interfering combustion gases are at low concentrations. The results showed that the measured temperature had an apparent oscillatory phenomenon due to combustion gases’ absorption and emission effects. This phenomenon tended to further strengthen with a thicker hot interfering ga...