New extended eddy dissipation concept model for flameless combustion in furnaces

Romero-Anton, Naiara; Huang, X.; Bao, Hesheng; Martin-Eskudero, Koldo; Salazar-Herran, Erik; Roekaerts, D.J.E.M.

doi:10.1016/j.combustflame.2020.06.025

New extended eddy dissipation concept model for flameless combustion in furnaces

Title

New extended eddy dissipation concept model for flameless combustion in furnaces

Author

Romero-Anton, Naiara (University of the Basque Country)
Huang, X. (TU Delft Fluid Mechanics)
Bao, Hesheng (Eindhoven University of Technology)
Martin-Eskudero, Koldo (University of the Basque Country)
Salazar-Herran, Erik (University of the Basque Country)
Roekaerts, D.J.E.M. (TU Delft Fluid Mechanics; Eindhoven University of Technology)

Date

2020

Abstract

Flameless combustion, also called MILD combustion (Moderate or Intense Low Oxygen Dilution), is a technology that reduces NO_x emissions and improves combustion efficiency. Appropriate turbulence-chemistry interaction models are needed to address this combustion regime via computational modelling. Following a similar analysis to that used in the Extended EDC model (E-EDC), the purpose of the present work is to develop and test a Novel Extended Eddy Dissipation Concept model (NE-EDC) to be better able to predict flameless combustion. In the E-EDC and NE-EDC models, in order to consider the influence of the dilution on the reaction rate and temperature, the coefficients are considered to be space dependent as a function of the local Reynolds and Damköhler numbers. A comparative study of four models is carried out: the E-EDC and NE-EDC models, the EDC model with specific, fixed values of the model coefficients optimized for the current application, and the Flamelet Generated Manifold (FGM) model with pure fuel and air as boundary conditions for flamelet generation. The models are validated using experimental data of the Delft Lab Scale furnace (9 kW) burning Natural Gas (T = 446 K) and preheated air (T = 886 K) injected via separate jets, at an overall equivalence ratio of 0.8. among the considered models, the NE-EDC results show the best agreement with experimental data, with a slight improvement over the E-EDC model and a significant improvement over the EDC model with tuned constant coefficients and the FGM model.

Subject

CFD
Eddy Dissipation Concept
Flameless combustion
Flamelet Generation Manifold
Lab-scale furnace
MILD combustion

To reference this document use:

http://resolver.tudelft.nl/uuid:df347165-1790-45a9-aed7-d649e635e09f

DOI

https://doi.org/10.1016/j.combustflame.2020.06.025

Embargo date

2022-07-03

ISSN

0010-2180

Source

Combustion and Flame, 220, 49-62