Investigations on quantitative measurement of heat release rate using chemiluminescence in premixed methane-air flames

Abstract

Abstract Numerical and experimental studies on 1-D, steady premixed methane-air flames were performed to investigate the quantitative measurement of heat release rate (HRR) using chemiluminescence. A detailed reaction mechanism, incorporating sub-reaction models for excited state radicals (CH* and OH*) was employed in the numerical study. The numerical work utilized the CHEMKIN-PRO package to investigate the distribution rule of excited state radicals and HRR. The heat release characteristic of elementary reactions and the relationship between net reaction rate and HRR were analyzed as well. According to the result of numerical study, experimental work was conducted to measure the HRR and chemiluminescence of OH* and CH* in the flat flames. The distributions of HRR and chemiluminescent intensity were measured by high-accuracy coated Pt/13%-Rh-Pt thermocouple and ICCD camera, respectively. The results shows that OH* and CH* are located in the narrow area where severe chemical reactions occur with much heat release. Compared to CH*, OH* is more effective in marking the spatial distribution of HRR and the correlation between chemiluminescent intensity and HRR possesses characteristic of linearity. Thus, the HRR quantitative measurement method using chemiluminescence has been acquired.