A methane/air reaction mechanism is used to investigate NO formation at different pressures (l-3atm) and equivalent ratios (0.8-1.3). The NO concentration is evaluated by CHEMKIN premixed flame code and verified by NO-LIF experiment measurement. The results show the mechanism predicts reasonable NO formation at pressure of 1-3atm in fuel rich conditions (17% overestimated at 1aim and 20% underestimated at 3atm). From NO formation analysis in fuel rich conditions, the major contribution of NO is from thermal NO at 1800 K (61%) and decreases with temperatures (45% at 1500 K). The weighting of prompt NO in total NO formation is almost unchanged in different temperature. The importance of NNH mechanism is more significant at lower temperature (11% at 1800 K, 20% at 1500 K). Pressure has minor effect on the weighting of the different sources of NO formation. However, increasing of pressure increases the importance of N→H2CN→HCN→⋯→NO(3%at latm 11% at 3atm) and N2→CN→NCO→⋯→NO (37% at 1atm'48% at 3atm) formation pathways.
|Number of pages||7|
|Journal||Zhongguo Hangkong Taikong Xuehui Huikan/Transactions of the Aeronautical and Astronautical Society of the Republic of China|
|Publication status||Published - 2002 Dec 1|
All Science Journal Classification (ASJC) codes
- Aerospace Engineering