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Large Eddy Simulation of turbulent combustion in a stagnation point reverse flow combustor using detailed chemistry

Duwig, Christophe LU and Iudiciani, Piero LU (2014) In Fuel 123. p.256-273
Abstract
For meeting stringent emission restrictions, a modern solution is to operate in or close to the flameless mode. It implies a copious dilution of the reactants with vitiated gas resulting in low oxidant or fuel concentration and consequently low volumetric heat-release rate. On the contrary to traditional flames where heat release is occurring in very thin fronts, the flameless operation lies in the distributed reaction regime. Flameless operation is therefore associated with complex and non-linear interaction between mixing and chemical reactions. In this framework, this paper investigates turbulent combustion in a stagnation point reverse flow combustor and presents one of the first studies combining Large Eddy Simulation and detailed... (More)
For meeting stringent emission restrictions, a modern solution is to operate in or close to the flameless mode. It implies a copious dilution of the reactants with vitiated gas resulting in low oxidant or fuel concentration and consequently low volumetric heat-release rate. On the contrary to traditional flames where heat release is occurring in very thin fronts, the flameless operation lies in the distributed reaction regime. Flameless operation is therefore associated with complex and non-linear interaction between mixing and chemical reactions. In this framework, this paper investigates turbulent combustion in a stagnation point reverse flow combustor and presents one of the first studies combining Large Eddy Simulation and detailed chemistry for capturing the reaction and flow dynamics during flameless combustion. The paper reports a comprehensive sensitivity analysis where the effects of the numerical discretization grid, of the chemical mechanism, of the operation (premixed vs. non-premixed) and of the heat-losses at the walls are studied and compared. Further, the simulation results are compared with experimental data from the literature, giving confidence in the quality of the predictions. The reaction and flow dynamics are extracted from the results using modal analysis, showing rotational and helical structures. Finally, the distribution of intermediate species in the reaction layer is investigated bringing some new insights into the flameless combustion process and providing recommendations for further experimental investigations. (C) 2014 Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
Large Eddy Simulation (LES), Turbulent combustion, Flameless combustion, Distributed reaction regime, Detailed chemistry
in
Fuel
volume
123
pages
256 - 273
publisher
Elsevier
external identifiers
  • wos:000332403000032
  • scopus:84894084610
ISSN
1873-7153
DOI
10.1016/j.fuel.2014.01.072
language
English
LU publication?
yes
id
85c8cde3-b802-4a37-a3ae-1ac1df4b284e (old id 4417530)
date added to LUP
2014-04-30 11:56:29
date last changed
2017-09-10 03:52:27
@article{85c8cde3-b802-4a37-a3ae-1ac1df4b284e,
  abstract     = {For meeting stringent emission restrictions, a modern solution is to operate in or close to the flameless mode. It implies a copious dilution of the reactants with vitiated gas resulting in low oxidant or fuel concentration and consequently low volumetric heat-release rate. On the contrary to traditional flames where heat release is occurring in very thin fronts, the flameless operation lies in the distributed reaction regime. Flameless operation is therefore associated with complex and non-linear interaction between mixing and chemical reactions. In this framework, this paper investigates turbulent combustion in a stagnation point reverse flow combustor and presents one of the first studies combining Large Eddy Simulation and detailed chemistry for capturing the reaction and flow dynamics during flameless combustion. The paper reports a comprehensive sensitivity analysis where the effects of the numerical discretization grid, of the chemical mechanism, of the operation (premixed vs. non-premixed) and of the heat-losses at the walls are studied and compared. Further, the simulation results are compared with experimental data from the literature, giving confidence in the quality of the predictions. The reaction and flow dynamics are extracted from the results using modal analysis, showing rotational and helical structures. Finally, the distribution of intermediate species in the reaction layer is investigated bringing some new insights into the flameless combustion process and providing recommendations for further experimental investigations. (C) 2014 Elsevier Ltd. All rights reserved.},
  author       = {Duwig, Christophe and Iudiciani, Piero},
  issn         = {1873-7153},
  keyword      = {Large Eddy Simulation (LES),Turbulent combustion,Flameless combustion,Distributed reaction regime,Detailed chemistry},
  language     = {eng},
  pages        = {256--273},
  publisher    = {Elsevier},
  series       = {Fuel},
  title        = {Large Eddy Simulation of turbulent combustion in a stagnation point reverse flow combustor using detailed chemistry},
  url          = {http://dx.doi.org/10.1016/j.fuel.2014.01.072},
  volume       = {123},
  year         = {2014},
}