Session: 04-16 Hydrogen Emissions I

Submission Number: 178218

Investigating Flame Stabilization and Emissions of NO in a Low-Swirl H2 Micromix Burner Using LES 

Flame stabilization and nitrogen oxide (NO) emissions of a
low-swirl H2 burner, compatible with premixed operation and two
distinct micromix (MMX) injections, are presented using large-
eddy simulations (LES). The LES, which employ a partially stirred
reactor model, show satisfactory agreement with experimental
OH-planar laser-induced fluorescence measurements. The sim-
ulations reveal distinct combustion characteristics for each in-
jection strategy, as follows. A reference fully premixed case sta-
bilizes in an attached crown shape, and achieves the lowest NO
emissions. In the Var1.1 MMX injection strategy, H2 is conveyed
through narrow channels in the swirler blades, and injected both
inward, downstream of a turbulence generation plate, and out-
ward, downstream of the swirler. This case features a fuel-rich
central region engulfed in a lean outer region, and a reduced
swirl number, ultimately leading to elevated temperatures and an
increase in thermal NO. In the Var1.2 MMX configuration, the
fuel is introduced through an array of sub-millimeter channels,
upstream of the combustion chamber dump plane, causing intense
turbulent mixing. Two cases were considered for this approach,
with 70% and 30% of the H2 injected through these channels, re-
spectively, while the rest is fully premixed into the air crossflow.
The micromix fuel ratio (MFR) here provides leverage over the
intensity of flame attachment, with the larger MFR reducing the
thermal load on the rim. Increasing the MFR did not increase NO
emissions, as the augmented jet penetration limits entrapment of
fuel within vortices shed from the rim.

Presenting Author: Alexandre Barsse Polytechnique Montréal

Presenting Author Biography: PhD student at Polytechnique Montréal,
Supervised by Bruno Savard,
Co-Supervised by Patrizio Vena, National Research Council Canada

Authors:

Alexandre Barsse Polytechnique Montréal
Antoine Durocher National Research Council Canada
Luming Fan Shanghai Jiao Tong University
Sean Yun National Research Council Canada
Patrizio Vena National Research Council Canada
Bruno Savard Polytechnique Montréal