Product gas characteristics of strain stabilized ammonia/air premixed laminar flames

Recently ammonia has attracted interest as a hydrogen energy carrier as well as a carbon-free fuel. Fundamental combustion characteristics of ammonia mixtures, such as the laminar burning velocity and ignition characteristics, have been clarified. However, product gas characteristics which are important for the use of ammonia in combustors have not been clarified because of difficulty of experimentation. In this study, product gas characteristics of strain stabilized ammonia/air premixed laminar flames were experimentally investigated. An FTIR gas analyzer were employed for gas analysis. Although required amount of sampling gas for FTIR gas analyzer is relatively large, it could be reduced using the dilution sampling method. As a result, product gas characteristics from lean to rich ammonia/air flames were evaluated. Then, analysis of the chemical kinetics of ammonia/air flames was performed using the detailed reaction mechanism developed by Okafor et al. The results showed that some important reactions may need to be updated for accurate modelling of the product gas characteristics.