First- and second-order elliptic conditional moment closure calculations of piloted methane diffusion flames
- Energy and Resources Research Institute, School of Process, Environmental and Materials Engineering, University of Leeds, Leeds LS2 9JT (United Kingdom)
Presented are results obtained from the application of a first- and higher-order conditional moment closure (CMC) approach to the modeling of three methane diffusion flames at differing levels of local extinction. In addition to the analysis of higher-order chemistry applications, the results obtained from an elliptic formulation of the CMC equation are considered next to parabolic results presented in previous work. All predictions are based upon second-moment turbulence and scalar-flux closures, and the chemistry applied to represent mean production rates of species is a 16-step reduced mechanism. A second-order chemistry is implemented on the basis of a two-step kinetic representation of methane combustion, used to correct first-order rates. In general, predictions obtained using the second-order model improve significantly upon first-order results for both major and minor species under fuel-rich conditions. The simplified chemistry employed does not however fully capture the effects of local extinction, and suggestions are made regarding the further developments required to permit the accurate prediction of highly strained flames using CMC methods. (author)
- OSTI ID:
- 20919413
- Journal Information:
- Combustion and Flame, Vol. 150, Issue 1-2; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
- Country of Publication:
- United States
- Language:
- English
Similar Records
Conditional moment closure calculations of a swirl-stabilized, turbulent nonpremixed methane flame
Assessment of closure schemes in second-order conditional moment closure against DNS with extinction and ignition