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Title: A direct numerical simulation study of flame structure and stabilization of an experimental high Ka CH4/air premixed jet flame

Abstract

In the present work, a direct numerical simulation (DNS) of an experimental high Karlovitz number (Ka) CH4/air piloted premixed flame was analyzed to study the inner structure and the stabilization mechanism of the turbulent flame. A reduced chemical mechanism for premixed CH4/air combustion with NOx based on GRI-Mech3.0 was used, including 268 elementary reactions and 28 transported species. The evolution of the stretch factor, I0, indicates that the burning rate per unit flame surface area is considerably reduced in the near field and exhibits a minimum at x/D = 8. Downstream, the burning rate gradually increases. The stretch factor is different between different species, suggesting the quenching of some reactions but not others. Comparison between the turbulent flame and strained laminar flames indicates that certain aspects of the mean flame structure can be represented surprisingly well by flamelets if changes in boundary conditions are accounted for and the strain rate of the mean flow is employed; however, the thickening of the flame due to turbulence is not captured. The spatial development of displacement speeds is studied at higher Ka than previous DNS. In contrast to almost all previous studies, the mean displacement speed conditioned on the flame front is negativemore » in the near field, and the dominant contribution to the displacement speed is normal diffusion with the reaction contribution being secondary. Further downstream, reaction overtakes normal diffusion, contributing to a positive displacement speed. The negative displacement speed in the near field implies that the flame front situates itself in the pilot region where the inner structure of the turbulent flame is affected significantly, and the flame stabilizes in balance with the inward flow. Notably, in the upstream region of the turbulent flame, the main reaction contributing to the production of OH, H+O2⇌O+OH (R35), is weak. Moreover, oxidation reactions, H2+OH⇌H+H2O (R79) and CO+OH⇌CO2+H (R94), are influenced by H2O and CO2 from the pilot and are completely quenched. Hence, the entire radical pool of OH, H and O is affected. Furthermore, the fuel consumption layer remains comparably active and generates heat, mainly via the reaction CH4+OH⇌CH3+H2O (R93).« less

Authors:
 [1];  [1];  [2]
  1. The Univ. of New South Wales, NSW (Australia)
  2. Sandia National Lab. (SNL-CA), Livermore, CA (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1361216
Alternate Identifier(s):
OSTI ID: 1419138
Report Number(s):
SAND-2017-2196J
Journal ID: ISSN 0010-2180; PII: S001021801730069X
Grant/Contract Number:  
AC04-94AL85000; AC04-94-AL85000
Resource Type:
Accepted Manuscript
Journal Name:
Combustion and Flame
Additional Journal Information:
Journal Volume: 180; Journal Issue: C; Journal ID: ISSN 0010-2180
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; direct numerical simulation; turbulent flame; flame structure; displacement speed; reaction rate

Citation Formats

Wang, Haiou, Hawkes, Evatt R., and Chen, Jacqueline H. A direct numerical simulation study of flame structure and stabilization of an experimental high Ka CH4/air premixed jet flame. United States: N. p., 2017. Web. doi:10.1016/j.combustflame.2017.02.022.
Wang, Haiou, Hawkes, Evatt R., & Chen, Jacqueline H. A direct numerical simulation study of flame structure and stabilization of an experimental high Ka CH4/air premixed jet flame. United States. https://doi.org/10.1016/j.combustflame.2017.02.022
Wang, Haiou, Hawkes, Evatt R., and Chen, Jacqueline H. Fri . "A direct numerical simulation study of flame structure and stabilization of an experimental high Ka CH4/air premixed jet flame". United States. https://doi.org/10.1016/j.combustflame.2017.02.022. https://www.osti.gov/servlets/purl/1361216.
@article{osti_1361216,
title = {A direct numerical simulation study of flame structure and stabilization of an experimental high Ka CH4/air premixed jet flame},
author = {Wang, Haiou and Hawkes, Evatt R. and Chen, Jacqueline H.},
abstractNote = {In the present work, a direct numerical simulation (DNS) of an experimental high Karlovitz number (Ka) CH4/air piloted premixed flame was analyzed to study the inner structure and the stabilization mechanism of the turbulent flame. A reduced chemical mechanism for premixed CH4/air combustion with NOx based on GRI-Mech3.0 was used, including 268 elementary reactions and 28 transported species. The evolution of the stretch factor, I0, indicates that the burning rate per unit flame surface area is considerably reduced in the near field and exhibits a minimum at x/D = 8. Downstream, the burning rate gradually increases. The stretch factor is different between different species, suggesting the quenching of some reactions but not others. Comparison between the turbulent flame and strained laminar flames indicates that certain aspects of the mean flame structure can be represented surprisingly well by flamelets if changes in boundary conditions are accounted for and the strain rate of the mean flow is employed; however, the thickening of the flame due to turbulence is not captured. The spatial development of displacement speeds is studied at higher Ka than previous DNS. In contrast to almost all previous studies, the mean displacement speed conditioned on the flame front is negative in the near field, and the dominant contribution to the displacement speed is normal diffusion with the reaction contribution being secondary. Further downstream, reaction overtakes normal diffusion, contributing to a positive displacement speed. The negative displacement speed in the near field implies that the flame front situates itself in the pilot region where the inner structure of the turbulent flame is affected significantly, and the flame stabilizes in balance with the inward flow. Notably, in the upstream region of the turbulent flame, the main reaction contributing to the production of OH, H+O2⇌O+OH (R35), is weak. Moreover, oxidation reactions, H2+OH⇌H+H2O (R79) and CO+OH⇌CO2+H (R94), are influenced by H2O and CO2 from the pilot and are completely quenched. Hence, the entire radical pool of OH, H and O is affected. Furthermore, the fuel consumption layer remains comparably active and generates heat, mainly via the reaction CH4+OH⇌CH3+H2O (R93).},
doi = {10.1016/j.combustflame.2017.02.022},
journal = {Combustion and Flame},
number = C,
volume = 180,
place = {United States},
year = {Fri Mar 17 00:00:00 EDT 2017},
month = {Fri Mar 17 00:00:00 EDT 2017}
}

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Cited by: 47 works
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Works referenced in this record:

Fuel Flexibility Influences on Premixed Combustor Blowout, Flashback, Autoignition, and Stability
journal, January 2008

  • Lieuwen, Tim; McDonell, Vince; Petersen, Eric
  • Journal of Engineering for Gas Turbines and Power, Vol. 130, Issue 1
  • DOI: 10.1115/1.2771243

High Resolution PIV and CH-PLIF Measurements and Analysis of a Shear Layer Stabilized Flame
conference, June 2015

  • Foley, C. W.; Chterev, I.; Seitzman, J.
  • Volume 4B: Combustion, Fuels and Emissions
  • DOI: 10.1115/GT2015-43387

Investigation of scalar mixing in the thin reaction zones regime using a simultaneous CH-LIF/Rayleigh laser technique
journal, January 1998

  • Mansour, Mohy S.; Peters, Norbert; Chen, Yung-Cheng
  • Symposium (International) on Combustion, Vol. 27, Issue 1
  • DOI: 10.1016/S0082-0784(98)80471-2

A new piloted premixed jet burner to study strong finite-rate chemistry effects
journal, October 2007


From Large-Eddy Simulation to Direct Numerical Simulation of a lean premixed swirl flame: Filtered laminar flame-PDF modeling
journal, July 2011


Experimental measurements of geometric properties of turbulent stratified flames
journal, January 2009

  • Anselmo-Filho, P.; Hochgreb, S.; Barlow, R. S.
  • Proceedings of the Combustion Institute, Vol. 32, Issue 2
  • DOI: 10.1016/j.proci.2008.05.085

Effects of preferential transport in turbulent bluff-body-stabilized lean premixed CH4/air flames
journal, August 2012


The asymptotic structure of stoichiometric methaneair flames
journal, May 1987


The inner structure of methaneair flames
journal, August 1990


Progress in knowledge of flamelet structure and extinction
journal, August 2000


Strained Premixed Laminar Flames Under Nonadiabatic Conditions
journal, March 1983


Extinction of Strained Premixed Propane-air Flames with Complex Chemistry
journal, August 1988

  • Darabiha, N.; Candel, S. M.; Giovangigli, V.
  • Combustion Science and Technology, Vol. 60, Issue 4-6
  • DOI: 10.1080/00102208808923988

Response and flamelet structure of stretched premixed methaneair flames
journal, July 1988


Effect of the composition of the hot product stream in the quasi-steady extinction of strained premixed flames
journal, November 2010


Dynamics and structure of unsteady, strained, laminar premixed flames
journal, January 1994


Unsteady strain rate and curvature effects in turbulent premixed methane-air flames
journal, July 1996


Premixed flame response to unsteady strain rate and curvature
journal, July 1997


The turbulent burning velocity for large-scale and small-scale turbulence
journal, April 1999


Negative flame speed in an unsteady 2-D premixed flame: A computational study
journal, January 1996

  • Gran, Inge R.; Echekki, Tarek; Chen, Jacqueline H.
  • Symposium (International) on Combustion, Vol. 26, Issue 1
  • DOI: 10.1016/S0082-0784(96)80232-3

Analysis of the contribution of curvature to premixed flame propagation
journal, July 1999


Direct numerical simulation of hydrogen-enriched lean premixed methane–air flames
journal, August 2004


Comparison of direct numerical simulation of lean premixed methane–air flames with strained laminar flame calculations
journal, January 2006


Correlation of flame speed with stretch in turbulent premixed methane/air flames
journal, January 1998


Unsteady effects of strain rate and curvature on turbulent premixed flames in an inflow–outflow configuration
journal, April 2004


Premixed flame propagation in turbulent flow by means of stereoscopic PIV and dual-plane OH-PLIF at sustained kHz repetition rates
journal, January 2013


Effect of quenching of the oxidation layer in highly turbulent counterflow premixed flames
journal, January 2011

  • Coriton, Bruno; Frank, Jonathan H.; Hsu, Andrea G.
  • Proceedings of the Combustion Institute, Vol. 33, Issue 1
  • DOI: 10.1016/j.proci.2010.05.028

Petascale direct numerical simulation of turbulent combustion—fundamental insights towards predictive models
journal, January 2011


Turbulence–flame interactions in lean premixed hydrogen: transition to the distributed burning regime
journal, May 2011

  • Aspden, A. J.; Day, M. S.; Bell, J. B.
  • Journal of Fluid Mechanics, Vol. 680
  • DOI: 10.1017/jfm.2011.164

Flame structure analysis for categorization of lean premixed CH4/air and H2/air flames at high Karlovitz numbers: Direct numerical simulation studies
journal, January 2015

  • Carlsson, Henning; Yu, Rixin; Bai, Xue-Song
  • Proceedings of the Combustion Institute, Vol. 35, Issue 2
  • DOI: 10.1016/j.proci.2014.09.002

Differential diffusion effects, distributed burning, and local extinctions in high Karlovitz premixed flames
journal, September 2015


Interactions between turbulence and flames in premixed reacting flows
journal, December 2011

  • Hamlington, Peter E.; Poludnenko, Alexei Y.; Oran, Elaine S.
  • Physics of Fluids, Vol. 23, Issue 12
  • DOI: 10.1063/1.3671736

Structure of a spatially developing turbulent lean methane–air Bunsen flame
journal, January 2007

  • Sankaran, Ramanan; Hawkes, Evatt R.; Chen, Jacqueline H.
  • Proceedings of the Combustion Institute, Vol. 31, Issue 1
  • DOI: 10.1016/j.proci.2006.08.025

Response of flame thickness and propagation speed under intense turbulence in spatially developing lean premixed methane–air jet flames
journal, September 2015


A petascale direct numerical simulation study of the modelling of flame wrinkling for large-eddy simulations in intense turbulence
journal, August 2012


On the fractal characteristics of low Damköhler number flames
journal, November 2013


Distributed reactions in highly turbulent premixed methane/air flames
journal, July 2015


Direct numerical simulations of a high Karlovitz number laboratory premixed jet flame – an analysis of flame stretch and flame thickening
journal, February 2017

  • Wang, Haiou; Hawkes, Evatt R.; Chen, Jacqueline H.
  • Journal of Fluid Mechanics, Vol. 815
  • DOI: 10.1017/jfm.2017.53

Terascale direct numerical simulations of turbulent combustion using S3D
journal, January 2009


Several new numerical methods for compressible shear-layer simulations
journal, June 1994


Low-storage, explicit Runge–Kutta schemes for the compressible Navier–Stokes equations
journal, November 2000

  • Kennedy, Christopher A.; Carpenter, Mark H.; Lewis, R. Michael
  • Applied Numerical Mathematics, Vol. 35, Issue 3
  • DOI: 10.1016/S0168-9274(99)00141-5

Impact of multi-component diffusion in turbulent combustion using direct numerical simulations
journal, November 2015


Turbulent burning velocity measurements: Extended to extreme levels of turbulence
journal, January 2017

  • Wabel, Timothy M.; Skiba, Aaron W.; Driscoll, James F.
  • Proceedings of the Combustion Institute, Vol. 36, Issue 2
  • DOI: 10.1016/j.proci.2016.08.013

Turbulent premixed combustion: Flamelet structure and its effect on turbulent burning velocities
journal, February 2008


The evolution equation for the flame surface density in turbulent premixed combustion
journal, November 1994


Direct numerical simulation of H 2 /O 2 /N 2 flames with complex chemistry in two-dimensional turbulent flows
journal, December 1994


Preferential diffusion effects on the burning rate of interacting turbulent premixed hydrogen-air flames
journal, November 2002


Strained flamelets for turbulent premixed flames, I: Formulation and planar flame results
journal, May 2010


LES of a premixed jet flame DNS using a strained flamelet model
journal, December 2013


Strain Characteristics Near the Flame Attachment Point in a Swirling Flow
journal, April 2011


Turbulence-flame interactions in DNS of a laboratory high Karlovitz premixed turbulent jet flame
journal, September 2016

  • Wang, Haiou; Hawkes, Evatt R.; Chen, Jacqueline H.
  • Physics of Fluids, Vol. 28, Issue 9
  • DOI: 10.1063/1.4962501

Stretch effects on the burning velocity of turbulent premixed hydrogen/air flames
journal, January 2000


Dynamic behavior of premixed flame fronts in laminar and turbulent flows
journal, January 1985


Effects of flow transients on the burning velocity of laminar hydrogen/air premixed flames
journal, January 2000


Works referencing / citing this record:

Vitiated High Karlovitz n-decane/air Turbulent Flames: Scaling Laws and Micro-mixing Modeling Analysis
journal, July 2018

  • Bouaniche, Alexandre; Jaouen, Nicolas; Domingo, Pascale
  • Flow, Turbulence and Combustion, Vol. 102, Issue 1
  • DOI: 10.1007/s10494-018-9946-y