Transition from momentum to buoyancy-controlled turbulent jet diffusion flames and flame height relationships

Journal Article · Mon Mar 01 00:00:00 EST 1993 · Combustion and Flame; (United States)

DOI:https://doi.org/10.1016/0010-2180(93)90148-V· OSTI ID:6442088

Delichatsios, M A ^[1]

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1. Factory Mutual Research Corp., Norwood, MA (United States)

Based on dimensional arguments for the physics in turbulent diffusion flames, an analysis is presented for the transition characteristics from momentum-to buoyancy-controlled turbulent jet diffusion flames. This analysis extends previous correlations and investigations on the dynamics of buoyant jet flames and pool fires. A new correlation is derived and compared with experiments for flame heights in turbulent diffusion jet flames ranging from buoyancy-to momentum-dominated cases. The same methodology is used of recorrelating entrainment rates in turbulent diffusion flames, buoyancy or momentum dominated. The present results have been used to delineate various regimes characteristic of jet diffusion flames such as laminar, turbulent, buoyancy-dominated, momentum-dominated, and lift-off (turbulent jet) flames. Differences and similarities between the present approach and published results are also discussed. A practical contribution is the enhancement of the classical Hottel and Hawthorne laminar-turbulent transition plot by emphasizing that, in most cases, prior to the turbulent momentum regime there exists a considerable turbulent buoyant regime.

• OSTI ID: 6442088
• Journal Information: Combustion and Flame; (United States), Vol. 92:4; ISSN 0010-2180
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
FLAMES
FLUID MECHANICS
COMBUSTION KINETICS
CORRELATIONS
DIFFUSION
GEOMETRY
JETS
LAMINAR FLOW
TURBULENT FLOW
CHEMICAL REACTION KINETICS
FLUID FLOW
KINETICS
MATHEMATICS
MECHANICS
REACTION KINETICS
400800* - Combustion
Pyrolysis
& High-Temperature Chemistry