TY - JOUR
T1 - Determination, correlation, and mechanistic interpretation of effects of hydrogen addition on laminar flame speeds of hydrocarbon-air mixtures
AU - Tang, C. L.
AU - Huang, Z. H.
AU - Law, C. K.
N1 - Funding Information:
The work at the Xian Jiaotong University was supported by the National Natural Science Foundation of China ( 50636040 and 50821604 ) and National Basic Research Project ( 2007CB210006 ). The work at Princeton University was supported by the Combustion Energy Frontier Research Center, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001198. The authors thank Andrew P. Kelley, Yuyang Li, and Fujia Wu for their contributions to this study.
PY - 2011
Y1 - 2011
N2 - The stretch-affected propagation speeds of expanding spherical flames of n-butane-air mixtures with hydrogen addition were measured at atmospheric pressure and subsequently processed through a nonlinear regression analysis to yield the stretch-free laminar flame speeds. Based on a hydrogen addition parameter (RH) and an effective fuel equivalence ratio (φF), these laminar flame speeds were found to increase almost linearly with RH, for φF between 0.6 and 1.4 and RH from 0 to 0.5, with the slope of the variation assuming a minimum around stoichiometry. These experimental results also agree well with computed values using a detailed reaction mechanism. Furthermore, a mechanistic investigation aided by sensitivity analysis identified that kinetic effects through the global activation energy, followed by thermal effects through the adiabatic flame temperature, have the most influence on the increase in the flame speeds and the associated linear variation with RH due to hydrogen addition. Nonequidiffusion effects due to the high mobility of hydrogen, through the global Lewis number, have the least influence. Further calculations for methane, ethene, and propane as the fuel showed similar behavior, leading to possible generalization of the phenomena and correlation.
AB - The stretch-affected propagation speeds of expanding spherical flames of n-butane-air mixtures with hydrogen addition were measured at atmospheric pressure and subsequently processed through a nonlinear regression analysis to yield the stretch-free laminar flame speeds. Based on a hydrogen addition parameter (RH) and an effective fuel equivalence ratio (φF), these laminar flame speeds were found to increase almost linearly with RH, for φF between 0.6 and 1.4 and RH from 0 to 0.5, with the slope of the variation assuming a minimum around stoichiometry. These experimental results also agree well with computed values using a detailed reaction mechanism. Furthermore, a mechanistic investigation aided by sensitivity analysis identified that kinetic effects through the global activation energy, followed by thermal effects through the adiabatic flame temperature, have the most influence on the increase in the flame speeds and the associated linear variation with RH due to hydrogen addition. Nonequidiffusion effects due to the high mobility of hydrogen, through the global Lewis number, have the least influence. Further calculations for methane, ethene, and propane as the fuel showed similar behavior, leading to possible generalization of the phenomena and correlation.
KW - Hydrogen addition
KW - Laminar flame speed
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U2 - 10.1016/j.proci.2010.05.039
DO - 10.1016/j.proci.2010.05.039
M3 - Article
AN - SCOPUS:78650875170
SN - 1540-7489
VL - 33
SP - 921
EP - 928
JO - Proceedings of the Combustion Institute
JF - Proceedings of the Combustion Institute
IS - 1
ER -