The effect of strain rate on NOx emissions in a methane air counterflow diffusion flame is numerically analyzed with detailed chemistry. First, the kinetic mechanism is revised and tested by introducing ammonia into the fuel. Comparison of the experimental results with the computed results showed that NO formation is well predicted by the present detailed chemistry. NOx formation at high air temperature is then calculated by increasing the strain rate from 10 s-1 to 12 800 s-1. The results showed that NOx emission decreases dramatically with the increase of strain rate and that extinction limit is greatly extended with the increase of air temperature. Furthermore, the sensitivity and production rate analyses are made. Important elementary reactions and formation routes corresponding to NOx emissions at different strain rates are presented and discussed. Comparisons between prompt NOx and thermal NOx are made. Quenches of thermal NOx and NCO and CN recycle routes at high strain rate are identified.
|Original language||English (US)|
|Number of pages||7|
|Journal||Nippon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B|
|State||Published - 1996|
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanical Engineering