Modeling and calculation of turbulent lifted diffusion flames

Journal Article · Fri Dec 31 23:00:00 EST 1993 · Combustion and Flame; (United States)

DOI:https://doi.org/10.1016/0010-2180(94)90155-4· OSTI ID:5488011

Sanders, J P.H.; Lamers, A P.G.G. ^[1]

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1. Eindhoven Univ. of Technology (Netherlands). Faculty of Mechanical Engineering

Liftoff heights of turbulent diffusion flames have been modeled using the laminar diffusion flamelet concept of Peters and Williams. The strain rate of the smallest eddies is used as the stretch describing parameter, instead of the more common scalar dissipation rate. The h(U) curve, which is the mean liftoff height as a function of fuel exit velocity can be accurately predicted, while this was impossible with the scalar dissipation rate. Liftoff calculations performed in the flames as well as in the equivalent isothermal jets, using a standard k-[epsilon] turbulence model yield approximately the same correct slope for the h(U) curve while the offset has to be reproduced by choosing an appropriate coefficient in the strain rate model. For the flame calculations a model for the pdf of the fluctuating flame base is proposed. The results are insensitive to its width. The temperature field is qualitatively different from the field calculated by Bradley et al. who used a premixed flamelet model for diffusion flames.

• OSTI ID: 5488011
• Journal Information: Combustion and Flame; (United States), Journal Name: Combustion and Flame; (United States) Vol. 96:1-2; ISSN CBFMAO; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
BURNERS
CHEMICAL REACTION KINETICS
COMBUSTION KINETICS
ENGINES
FLAMES
FLARING
FLUID FLOW
GAS TURBINE ENGINES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
KINETICS
REACTION KINETICS
STABILIZATION
TURBULENT FLOW