Etude de la combustion de gaz de synthèse issus d'un processus de ...

Experimental and numerical laminar syngas combustion
4.1.1.4 Laminar burning velocity
Fig. 4.18 gives the stretched laminar burning velocity versus the flame stretch rate for
typical syngas compositions.
The maximum value laminar burning velocity is presented at the stoichiometric
equivalence ratio, while lean or rich mixtures decrease the burning velocities.
Downdraft syngas composition shows the highest burning velocities for all the
equivalence ratios considered. The stretched burning velocity increases with the
increase of flame stretch rate for lean (φ=0.8) syngas-air mixtures. This behavior
remains for stoichiometric and rich (φ=1.2) mixtures in the case of updraft and
downdraft compositions. In opposite, burning velocity decreases with the increase of
stretch rate for stoichiometric fluidized syngas-air case.
tel-00623090, version 1 - 13 Sep 2011
Su (m/s)
0.4
φ =0.6
0.3
0.2
0.1
Updraft
Downdraft
0.0
0 50 100 150 200 250 300 350 400
κ (s -1 )
0.5
φ =0.8
0.4
Su (m/s)
0.3
0.2
0.1
0.0
Updraft
Dow ndraft
Fluidized
0 100 200 300 400 500 600
κ (s -1 )
Figure 4.18a – Stretched burning velocity versus stretch rate for syngas-air mixtures at various
equivalence ratios.
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