化学発光分光法による火炎温度の診断

抄録

To explore the behavior of near-extinction flamelets in turbulent premixed flames, emission intensities of OH, CH and C₂ radicals of hydrocarbon-air premixed flames have been examined using the newly developed emission spectroscopy system. It has been shown in our previous study that the emission intensity ratio of 515.5 nm/470.5 nm bands of C₂ radical uniquely depends on the temperature of unstrained methane/air and propane/air flames. In the present study, to establish the technique that estimates the temperature of the near-extinction flamelet of turbulent premixed flames, the relation between the temperature and the emission intensity ratio of 515.5 nm/470.5 nm bands of C₂ radical of strained flames has been sought by using a counter-flow burner. The unique relation between the flame temperature and the emission intensity ratio of 515.5 nm/470.5 nm bands of C₂ radical has been found to exist for the Propane-air and the Butane-air strained flames. Therefore, it can be concluded that the temperature of flamelets of the Propane-air and the Butane-air turbulent premixed flames can be estimated by using the relation between the temperature of the strained flame and the emission intensity ratio of 515.5 nm/470.5 nm bands of C₂ radical obtained in the present study.