Unsteady deflagration speed of an auto-ignitive dimethyl-ether (DME)/air mixture at stratified conditions

Desai, Swapnil S.; Sankaran, Ramanan; Im, Hong G.

doi:10.1016/j.proci.2018.09.019

Unsteady deflagration speed of an auto-ignitive dimethyl-ether (DME)/air mixture at stratified conditions

Journal Article · Fri Nov 09 00:00:00 EST 2018 · Proceedings of the Combustion Institute

DOI:https://doi.org/10.1016/j.proci.2018.09.019· OSTI ID:1784187

^[1]; ^[2]; ^[3]

Univ. of Tennessee, Knoxville, TN (United States)
Univ. of Tennessee, Knoxville, TN (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
King Abdullah Univ. of Science and Technology (KAUST), Thuwal (Saudi Arabia)

The propagation speed of an auto-ignitive dimethyl-ether (DME)/air mixture at elevated pressures and subjected to monochromatic temperature oscillations is numerically evaluated in a one-dimensional statistically stationary configuration using fully resolved numerical simulations with reduced kinetics and transport. Two sets of conditions with temperatures within and slightly above the negative temperature coefficient (NTC) regime are simulated to investigate the fundamental aspects of auto-ignition and flame propagation along with the transition from auto-ignitive deflagration to spontaneous propagation regimes under thermal stratification. Contrary to the standard laminar flame speed, the steady propagation speed of an auto-ignitive front is observed to scale proportionally to its level of upstream reactivity. It is shown that this interdependence is primarily influenced by the characteristic residence time and the homogeneous auto-ignition delay. Furthermore, the unsteady reaction front in either of the two cases responds distinctly to the imposed stratification. Specifically, the results in both cases show that the dynamic flame response depends on the mean temperature at the flame base T_b and the time-scale of thermal stratification. It is also found that, based on T_b and the propensity of the mixture to two-stage chemistry, the instantaneous peak propagation speed and the overall time taken to achieve that speed differs considerably. Here, a displacement speed analysis is carried out to elucidate the underlying combustion modes that are responsible for such a variation in flame response.

View Accepted Manuscript (DOE)

Research Organization:: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

Sponsoring Organization:: USDOE

Grant/Contract Number:: AC05-00OR22725

OSTI ID:: 1784187

Alternate ID(s):: OSTI ID: 1637110
OSTI ID: 1565736

Journal Information:: Proceedings of the Combustion Institute, Journal Name: Proceedings of the Combustion Institute Journal Issue: 4 Vol. 37; ISSN 1540-7489

Publisher:: ElsevierCopyright Statement

Country of Publication:: United States

Language:: English

References (28)

Integral Length Scales and Time Scales of Turbulence in an Optical Spark-Ignition Engine Aleiferis, P. G.; Behringer, M. K.; Malcolm, J. S. Flow, Turbulence and Combustion, Vol. 98, Issue 2 https://doi.org/10.1007/s10494-016-9775-9	journal	October 2016
Regime classification of an exothermic reaction with nonuniform initial conditions Zeldovich, Y. Combustion and Flame, Vol. 39, Issue 2 https://doi.org/10.1016/0010-2180(80)90017-6	journal	October 1980
Boundary conditions for direct simulations of compressible viscous flows Poinsot, T. J.; Lelef, S. K. Journal of Computational Physics, Vol. 101, Issue 1 https://doi.org/10.1016/0021-9991(92)90046-2	journal	July 1992
Theory of combustion waves in homogeneous media Merzhanov, A. G.; Khaikin, B. I. Progress in Energy and Combustion Science, Vol. 14, Issue 1 https://doi.org/10.1016/0360-1285(88)90006-8	journal	January 1988
Modes of reaction front propagation from hot spots Gu, X. J.; Emerson, D. R.; Bradley, D. Combustion and Flame, Vol. 133, Issue 1-2 https://doi.org/10.1016/S0010-2180(02)00541-2	journal	April 2003
Analysis of the contribution of curvature to premixed flame propagation Echekki, Tarek; Chen, Jacqueline H. Combustion and Flame, Vol. 118, Issue 1-2 https://doi.org/10.1016/S0010-2180(99)00006-1	journal	July 1999
Dynamic flammability limits of methane/air premixed flames with mixture composition fluctuations Sankaran, Ramanan; Im, Hong G. Proceedings of the Combustion Institute, Vol. 29, Issue 1 https://doi.org/10.1016/S1540-7489(02)80014-1	journal	January 2002
Transport budgets in turbulent lifted flames of methane autoigniting in a vitiated co-flow Gordon, Robert L.; Masri, Assaad R.; Pope, Stephen B. Combustion and Flame, Vol. 151, Issue 3 https://doi.org/10.1016/j.combustflame.2007.07.001	journal	November 2007
Autoignition and front propagation in low temperature combustion engine environments Bansal, Gaurav; Im, Hong G. Combustion and Flame, Vol. 158, Issue 11 https://doi.org/10.1016/j.combustflame.2011.03.019	journal	November 2011
Experimental analysis of propagation regimes during the autoignition of a fully premixed methane–air mixture in the presence of temperature inhomogeneities Strozzi, Camille; Mura, Arnaud; Sotton, Julien Combustion and Flame, Vol. 159, Issue 11 https://doi.org/10.1016/j.combustflame.2012.06.011	journal	November 2012
A DNS study of the ignition of lean PRF/air mixtures with temperature inhomogeneities under high pressure and intermediate temperature Kim, Seung Ook; Luong, Minh Bau; Chen, Jacqueline H. Combustion and Flame, Vol. 162, Issue 3 https://doi.org/10.1016/j.combustflame.2014.09.001	journal	March 2015
An experimental study of flame and autoignition interactions of iso-octane and air mixtures Assanis, Dimitris; Wagnon, Scott W.; Wooldridge, Margaret S. Combustion and Flame, Vol. 162, Issue 4 https://doi.org/10.1016/j.combustflame.2014.10.012	journal	April 2015
Flame dynamics in oscillating flows under autoignitive conditions Deng, Sili; Zhao, Peng; Mueller, Michael E. Combustion and Flame, Vol. 168 https://doi.org/10.1016/j.combustflame.2016.04.001	journal	June 2016
The role of low temperature chemistry in combustion mode development under elevated pressures Pan, Jiaying; Wei, Haiqiao; Shu, Gequn Combustion and Flame, Vol. 174 https://doi.org/10.1016/j.combustflame.2016.09.012	journal	December 2016
On the effect of injection timing on the ignition of lean PRF/air/EGR mixtures under direct dual fuel stratification conditions Luong, Minh Bau; Sankaran, Ramanan; Yu, Gwang Hyeon Combustion and Flame, Vol. 183 https://doi.org/10.1016/j.combustflame.2017.05.023	journal	September 2017
The structure and propagation of laminar flames under autoignitive conditions Krisman, Alex; Hawkes, Evatt R.; Chen, Jacqueline H. Combustion and Flame, Vol. 188 https://doi.org/10.1016/j.combustflame.2017.09.012	journal	February 2018
Direct numerical simulations of reacting flows with detailed chemistry using many-core/GPU acceleration Hernández Pérez, Francisco E.; Mukhadiyev, Nurzhan; Xu, Xiao Computers & Fluids, Vol. 173 https://doi.org/10.1016/j.compfluid.2018.03.074	journal	September 2018
An optical study of in-cylinder CH2O and OH chemiluminescence in flame-induced reaction front propagation using high speed imaging Ma, Xiao; Wang, Zhi; Jiang, Changzhao Fuel, Vol. 134 https://doi.org/10.1016/j.fuel.2014.06.002	journal	October 2014
The effects of non-uniform temperature distribution on the ignition of a lean homogeneous hydrogen–air mixture Sankaran, Ramanan; Im, Hong G.; Hawkes, Evatt R. Proceedings of the Combustion Institute, Vol. 30, Issue 1 https://doi.org/10.1016/j.proci.2004.08.176	journal	January 2005
Advanced compression-ignition engines—understanding the in-cylinder processes Dec, John E. Proceedings of the Combustion Institute, Vol. 32, Issue 2 https://doi.org/10.1016/j.proci.2008.08.008	journal	January 2009
Multi-timescale modeling of ignition and flame regimes of n-heptane-air mixtures near spark assisted homogeneous charge compression ignition conditions Ju, Yiguang; Sun, Wenting; Burke, Michael P. Proceedings of the Combustion Institute, Vol. 33, Issue 1 https://doi.org/10.1016/j.proci.2010.06.110	journal	January 2011
Classification of ignition regimes in HCCI combustion using computational singular perturbation Gupta, Saurabh; Im, Hong G.; Valorani, Mauro Proceedings of the Combustion Institute, Vol. 33, Issue 2 https://doi.org/10.1016/j.proci.2010.07.014	journal	January 2011
Combustion regime of a reacting front propagating into an auto-igniting mixture Martz, J. B.; Kwak, H.; Im, H. G. Proceedings of the Combustion Institute, Vol. 33, Issue 2 https://doi.org/10.1016/j.proci.2010.07.040	journal	January 2011
A numerical study of the autoignition of dimethyl ether with temperature inhomogeneities Zhang, Haoyang; Hawkes, Evatt R.; Chen, Jacqueline H. Proceedings of the Combustion Institute, Vol. 34, Issue 1 https://doi.org/10.1016/j.proci.2012.07.026	journal	January 2013
Multi-scale modeling of dynamics and ignition to flame transitions of high pressure stratified n-heptane/toluene mixtures Sun, Weiqi; Won, Sang Hee; Gou, Xiaolong Proceedings of the Combustion Institute, Vol. 35, Issue 1 https://doi.org/10.1016/j.proci.2014.05.141	journal	January 2015
Numerical and experimental investigation of turbulent DME jet flames Bhagatwala, Ankit; Luo, Zhaoyu; Shen, Han Proceedings of the Combustion Institute, Vol. 35, Issue 2 https://doi.org/10.1016/j.proci.2014.05.147	journal	January 2015
Effects of initial temperature on autoignition and detonation development in dimethyl ether/air mixtures with temperature gradient Dai, Peng; Qi, Chengken; Chen, Zheng Proceedings of the Combustion Institute, Vol. 36, Issue 3 https://doi.org/10.1016/j.proci.2016.08.014	journal	January 2017
Experimental metrics for identifying origins of combustion variability during spark-assisted compression ignition Reuss, D. L.; Kuo, T-W; Silvas, G. International Journal of Engine Research, Vol. 9, Issue 5 https://doi.org/10.1243/14680874JER01108	journal	October 2008

Cited By (3)

Numerical studies on autoignition and detonation development from a hot spot in hydrogen/air mixtures Gao, Yuan; Dai, Peng; Chen, Zheng Combustion Theory and Modelling, Vol. 24, Issue 2 https://doi.org/10.1080/13647830.2019.1674923	journal	October 2019
On the ambiguity of premixed flame thickness definition of highly pre-heated mixtures and its implication on turbulent combustion regimes Rauch, Andreas H.; Chelliah, Harsha K. Combustion Theory and Modelling, Vol. 24, Issue 4 https://doi.org/10.1080/13647830.2020.1722857	journal	February 2020
On the ambiguity of premixed flame thickness definition of highly pre-heated mixtures and its implication on turbulent combustion regimes Rauch, Andreas H.; Chelliah, Harsha K. Taylor & Francis https://doi.org/10.6084/m9.figshare.11821389.v2	text	January 2020

Similar Records

Unsteady deflagration speed of an auto-ignitive dimethyl-ether (DME)/air mixture at stratified conditions

Journal Article · Mon Dec 31 23:00:00 EST 2018 · Proceedings of the Combustion Institute · OSTI ID:1565736

Auto-ignitive deflagration speed of methane (CH₄) blended dimethyl-ether (DME)/air mixtures at stratified conditions

Journal Article · Wed Oct 23 20:00:00 EDT 2019 · Combustion and Flame · OSTI ID:1615991

Direct numerical simulation of an auto-ignitive turbulent flame in a stratified dimethyl-ether (DME)/air mixture

Conference · Thu Feb 28 23:00:00 EST 2019 · OSTI ID:1784182

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Deflagration
Flame dynamics
Flame speed
Spontaneous propagation
Thermal stratification

Unsteady deflagration speed of an auto-ignitive dimethyl-ether (DME)/air mixture at stratified conditions

Citation Formats

References (28)

Cited By (3)

Similar Records

Related Subjects