Influential factors of a novel colorimetric thermometry developed for the combustible gases

Temperature distribution characteristics are important for evaluating the combustion status, safety monitoring, and disaster diagnosis of combustible gases. Traditional colorimetric thermometry is difficult to measure the temperature of combustible gases for the lack of the grey-body in the burning processes. In the present study, a visible burning facility for combustible gases is designed, and the temperature characteristics are measured using an improved colorimetric pyrometer with auxiliary solid powders as a grey-body. In order to improve the temperature measurement accuracy of the system, the type, particle size, and concentration of the powders as well as the ignition delay time are studied. After many debugging experiments, it is found that the best measurement results are obtained for the 30/70 H$_2$/air mixture with the tungsten powder with the mean particle size of 7.9 $\mu$m, particle concentration of 21 g/m$^3$, and ignition delay time of 80 ms. The results are corroborated with the previous studies.