TY - JOUR
T1 - Experimental and computational study of nonpremixed ignition of dimethyl ether in counterflow
AU - Zheng, X. L.
AU - Lu, T. F.
AU - Law, C. K.
AU - Westbrook, C. K.
AU - Curran, H. J.
N1 - Funding Information:
This work at Princeton University was supported by the Army Research Office under the technical monitoring of Dr. D. Mann and by the Air Force Office of Scientific Research under the technical monitoring of Dr. Julian M. Tishkoff. The work at the Lawrence Livermore National Laboratory was carried out under the auspices of the U.S. Department of Energy under Contract No. W-7405-ENG-48, and was supported by the DOE Office of Transportation Technologies, Gurpreet Singh and John Garbak, program managers.
Publisher Copyright:
© 2004 The Combustion Institute. Published by Elsevier Inc. All rights reserved.
PY - 2005
Y1 - 2005
N2 - The ignition temperature of nitrogen-diluted dimethyl ether (DME) by heated air in counterflow was experimentally determined for DME concentration from 5.9% to 30%, system pressure from 1.5 to 3.0 atm, and pressure-weighted strain rate from 110 to 170 s-1. These experimental data were compared with two mechanisms that were, respectively, available in 1998 and 2003, with the latter being a substantially updated version of the former. The comparison showed that while the 1998-mechanism uniformly over-predicted the ignition temperature, the 2003-mechanism yielded a surprisingly close agreement for all experimental data. Sensitivity analysis for the near-ignition state based on both mechanisms identified the deficiencies of the 1998-mechanism, in particular, the specifics of the low-temperature cool flame chemistry in effecting ignition at higher temperatures, as the fuel stream is being progressively heated from its cold boundary to the high-temperature ignition region around the hot-stream boundary. The 2003-mechanism, consisting of 79 species and 398 elementary reactions, was then systematically simplified by using the directed relation graph method to a skeletal mechanism of 49 species and 251 elementary reactions, which in turn was simplified further by using computational singular perturbation method and quasisteady- state species assumption to a reduced mechanism consisting of 33 species and 28 lumped reactions. It was demonstrated that both the skeletal and reduced mechanisms mimicked the performance of the detailed mechanism with high accuracy.
AB - The ignition temperature of nitrogen-diluted dimethyl ether (DME) by heated air in counterflow was experimentally determined for DME concentration from 5.9% to 30%, system pressure from 1.5 to 3.0 atm, and pressure-weighted strain rate from 110 to 170 s-1. These experimental data were compared with two mechanisms that were, respectively, available in 1998 and 2003, with the latter being a substantially updated version of the former. The comparison showed that while the 1998-mechanism uniformly over-predicted the ignition temperature, the 2003-mechanism yielded a surprisingly close agreement for all experimental data. Sensitivity analysis for the near-ignition state based on both mechanisms identified the deficiencies of the 1998-mechanism, in particular, the specifics of the low-temperature cool flame chemistry in effecting ignition at higher temperatures, as the fuel stream is being progressively heated from its cold boundary to the high-temperature ignition region around the hot-stream boundary. The 2003-mechanism, consisting of 79 species and 398 elementary reactions, was then systematically simplified by using the directed relation graph method to a skeletal mechanism of 49 species and 251 elementary reactions, which in turn was simplified further by using computational singular perturbation method and quasisteady- state species assumption to a reduced mechanism consisting of 33 species and 28 lumped reactions. It was demonstrated that both the skeletal and reduced mechanisms mimicked the performance of the detailed mechanism with high accuracy.
KW - Dimethyl ether
KW - Ignition
KW - Reduced mechanism
UR - http://www.scopus.com/inward/record.url?scp=84964226776&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84964226776&partnerID=8YFLogxK
U2 - 10.1016/j.proci.2004.08.241
DO - 10.1016/j.proci.2004.08.241
M3 - Conference article
AN - SCOPUS:84964226776
SN - 1540-7489
VL - 30
SP - 1101
EP - 1109
JO - Proceedings of the Combustion Institute
JF - Proceedings of the Combustion Institute
IS - 1
T2 - 30th International Symposium on Combustion
Y2 - 25 July 2004 through 30 July 2004
ER -