Abstract Submitted for the DFD20 Meeting of The American Physical Society Enhanced Integral Burning Rate of Turbulent Premixed Flames Through Stratification1

Submitted for the DFD20 Meeting of The American Physical Society Enhanced Integral Burning Rate of Turbulent Premixed Flames Through Stratification1 SINA KHEIRKHAH, SAJJAD MOHAMMADNEJAD, LESLIE SACA, RAMIN HEYDARLAKI, University of British Columbia, QIANG AN, PATRIZIO VENA, SEAN YUN, National Research Council Canada, PHILIPPE VERSAILLES, GILLES BOURQUE, Siemens Energy — Burning rate of turbulent premixed flames with compositionally inhomogeneous mixtures were investigated experimentally. Hydrogen-enriched methane-air turbulent flames with a global fuel-air equivalence ratio of 0.8 were tested. Two nozzles, each containing 4 fuel/air injection lobes were used in the experiments. The lobes of the first nozzle are straight, while those of the second nozzle are not, producing a swirling motion. The fuel is injected through several small diameter holes into the lobes, generating stratified conditions. Simultaneous OH and CH2O Planar Laser Induced Fluorescence (PLIF) along with Stereoscopic Particle Image Velocimetry (SPIV) were performed for the reacting conditions. SPIV and acetone-PLIF experiments were conducted to study the background turbulent flow characteristics and fuel-air mixing of non-reacting flow, respectively. The results show that stratification can lead to broadening of the preheat layer and generation of shredded-like heat release rate structures. Despite featuring a small intensity of burning rate, the shredded flame structure can feature a relatively large integral burning rate. This suggests some degree of stratification may enhance the stratified flames integral burning rate. 1This work is financially supported by Mitacs and Siemens Energy. Sina Kheirkhah University of British Columbia Date submitted: 11 Sep 2020 Electronic form version 1.4