Assessment of the Eulerian particle flamelet model for nonpremixed turbulent jet flames

Journal Article · Tue Jul 15 00:00:00 EDT 2008 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2008.04.009· OSTI ID:21044884

Kim, Seong-Ku ^[1]; Kim, Yongmo ^[2]

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1. Space Propulsion Division, Korea Aerospace Research Institute, Daejeon 305-600 (Korea)
2. Department of Mechanical Engineering, Hanyang University, Seoul 133-701 (Korea)

Although the Eulerian particle flamelet model (EPFM) recently proposed by Barths et al. [Proc. Combust. Inst. 27 (1998) 1841-1847] has shown the potential capabilities to realistically predict detailed pollutant (NO{sub x}, soot) formation in a turbulent reacting flow occurring within practical combustion devices, there still exists room to improve the predicative capability in terms of local flame structure and turbulence-chemistry interaction. In this study, the EPFM approach was applied to simulate two turbulent nonpremixed jet flames of CO/H{sub 2}/N{sub 2} fuel having the same jet Reynolds number but different nozzle diameters, and the capability of predicting the NO{sub x} formation as well as both similarity of major species and sensitivity of minor species to fluid-dynamic scaling for the two flames has been assessed deeply in terms of both conditional and unconditional mean structures. The present results indicate that the original EPFM substantially overpredicts the conditional scalar dissipation rate at the downstream region and consequently underpredicts the streamwise decay of superequilibrium radical concentrations to the equilibrium state. In this study, in order to correctly estimate the averaged conditional scalar dissipation rate, a new modeling of the conditional scalar dissipation rate based on a least-squares fit through a mass weighted spatial distribution has been devised. In terms of both conditional and unconditional means, the EPFM utilizing this new procedure yields nearly the same results as the Lagrangian flamelet model, and provides closer agreement with experimental data than the original EPFM approach. (author)

• OSTI ID: 21044884
• Journal Information: Combustion and Flame, Vol. 154, Issue 1-2; Other Information: Elsevier Ltd. All rights reserved; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
NITROGEN OXIDES
LEAST SQUARE FIT
FLAMES
MATHEMATICAL MODELS
JETS
SCALARS
COMBUSTION
HYDROGEN
PARTICLES
SIZE
SPATIAL DISTRIBUTION
CHEMICAL REACTIONS
SOOT
TURBULENCE
COMBUSTORS
FUELS
NOZZLES
POLLUTANTS
RADICALS
SCALING LAWS
SENSITIVITY
SIMULATION
NITROGEN
CARBON MONOXIDE
Turbulent nonpremixed jet flames
Unsteady flamelet model
Scalar dissipation rate