Chemiluminescence of BO{sub 2} to map the creation of thermal NO in flames

Journal Article · Sun Feb 15 00:00:00 EST 2009 · Combustion and Flame

DOI:https://doi.org/10.1016/J.COMBUSTFLAME.2008.10.005· OSTI ID:21137920

Maligne, D ^[1]; Cessou, A; Stepowski, D ^[1]

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1. CORIA CNRS UMR6614, Site Universitaire du Madrillet, BP12, 76801 St Etienne du Rouvray Cedex (France)

The aim of this study is to detect and map the local conditions that generate thermal NO in flames. According to the Zeldovich mechanism, the formation of NO comes from the local conjunction of a high concentration of atomic oxygen and a temperature above a critical high level imposed by the high activation energy of the rate-limiting reaction. The green light emitted when a flame is seeded with boron salts is a chemiluminescence from the BO{sup *}{sub 2} that is chemically formed in its excited state when BO reacts with atomic oxygen. As the rate of this oxidation is also strongly increasing with temperature, the chemiluminescence of BO{sub 2} depends on the concentration of atomic oxygen and on the temperature in a way similar to the formation rate of thermal NO. This double analogy suggests the possibility of an experimental in situ simulation of the formation rate of thermal NO or at least the use of the chemiluminescence of BO{sub 2} to map the sites where thermal NO is being created. Spectroscopic experiments and comparisons with numerical simulations have been performed to test the feasibility of this technique in laminar premixed and diffusion methane/air flames. The agreement is good except in the burnt gases of fuel-rich flames. Imaging strategies with different spectral filters have been developed in the same flames to overcome the problem of interference from soot radiation in diffusion flames. (author)

• OSTI ID: 21137920
• Journal Information: Combustion and Flame, Vol. 156, Issue 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
NITRIC OXIDE
CHEMILUMINESCENCE
OXYGEN
LAMINAR FLAMES
AIR
METHANE
BORON OXIDES
VISIBLE RADIATION
ACTIVATION ENERGY
COMPARATIVE EVALUATIONS
EXCITED STATES
COMBUSTION KINETICS
DIFFUSION
OXIDATION
SIMULATION
SOOT
TEMPERATURE DEPENDENCE
FILTERS
INTERFERENCE
SYNTHESIS
ABUNDANCE
FEASIBILITY STUDIES