Lean limit phenomena

Technical Report · Tue Mar 01 04:00:00 EST 1983

OSTI ID:6593767

Law, C K

The influence of stretch and preferential diffusion on premixed flame extinction and stability was investigated via two model flame configurations, namely the stagnation flame and the bunsen flame. Using a counterflow burner and a stagnation flow burner with a water-cooled wall, the effect of downstream heat loss on the extinction of a stretched premixed flame investigated for lean and rich propane/air and methane/air mixtures. It was demonstrated that extinction by stretch alone is possible only when the deficient reactant is the less mobile one. When it is the more mobile one, downstream heat loss or incomplete reaction is also needed to achieve extinction. The local extinction of bunsen flame tips and edges of hydrocarbon/air premixtures was investigated using a variety of burners. Results show that, while for both rich propane/air and butane/air mixtures tip opening occurs at a constant fuel equivalence ratio of 1.44 and is therefore independent of the intensity, uniformity, and configuration of the approach flow, for rich methane/air flames burning is intensified at the tip and therefore opening is not possible.

• Research Organization: Northwestern Univ., Evanston, IL (USA)
• OSTI ID: 6593767
• Report Number(s): N-83-29229
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400800* -- Combustion
Pyrolysis
& High-Temperature Chemistry
AIR
ALKANES
BURNERS
CHEMICAL REACTIONS
COMBUSTION
DIFFUSION
DISPERSIONS
FLAMES
FLUIDS
GASES
HYDROCARBONS
INHIBITION
MIXTURES
ORGANIC COMPOUNDS
OXIDATION
PROPANE
STABILITY
THERMOCHEMICAL PROCESSES