The design and commissioning of an enclosed jet-in-hot-coflow setup for the investigation of flameless combustion

Flameless combustion is a combustion regime which results in drastically lower 𝑁𝑂𝑥 emissions. 𝑁𝑂𝑥 has been found to influence global warming through its interactions with ozone chemistry and, exposure to this gas has been found to have adverse health effects on humans. The jet-in-hot-coflow design...

Modelling of MILD combustion in a lab-scale furnace with an extended FGM model including turbulence–radiation interaction

The flamelet generated manifold (FGM) model is suitable for moderate or intense low oxygen dilution (MILD) combustion provided the flamelets underlying the manifold include the effects of strong dilution by products of the fuel/oxidizer mixture. Here we propose such an extended model based on the use of non-premixed flamelets diluted at the...

Direct numerical simulations of flameless combustion

In this chapter, the research dedicated to moderate or intense low-oxygen dilution (MILD) combustion (also called flameless combustion) that relied on direct numerical simulations (DNS) is summarized. In particular, the various DNS carried out are detailed and three different configurations are considered: the autoigniting mixing layer...

SGS Reaction rate modelling for MILD combustion based on machine-learning combustion mode classification: Development and a priori study

A neural network (NN) aided model is proposed for the filtered reaction rate in moderate or intense low-oxygen dilution (MILD) combustion. The framework of the present model is based on the partially stirred reactor (PaSR) approach, and the fraction of the reactive structure appearing in the PaSR is predicted using different NN's, to consider...

Emission Modelling from a Multi-Fuel Dual Combustor Gas Turbine

Future transport and energy systems will still rely on gas turbines for energy conversion. The contribution of aviation to the emission of greenhouse gases and other pollutant species is predicted to increase in the near future, both in absolute quantities as well as relative to other sources. Despite historically being one of the greatest...

New extended eddy dissipation concept model for flameless combustion in furnaces

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...

Modeling Pollutant Emissions of Flameless Combustion With a Joint CFD and Chemical Reactor Network Approach

The Flameless Combustion (FC) regime has been pointed out as a promising combustion technique to lower the emissions of nitrogen oxides (NOx) while maintaining low CO and soot emissions, as well as high efficiencies. However, its accurate modeling remains a challenge. The prediction of pollutant species, especially NOx, is affected by the...

Flameless combustion and its potential towards gas turbines

Since its discovery, the Flameless Combustion (FC) regime has been seen as a promising alternative combustion technique to reduce pollutant emissions of gas turbine engines. This combustion mode is often characterized by well-distributed reaction zones, which can potentially decrease temperature gradients, acoustic oscillations and,...

Development and Validation of a New Eddy Dissipation Concept (EDC) Model for MILD Combustion

Moderate and Intense Low-oxygen Dilution (MILD) combustion is established to achieve high thermal efficiency and low pollutant emissions, including both NOx and soot. The Eddy Dissipation Concept (EDC) is the most widely used combustion model in the existing numerical studies of turbulent MILD combustion. It is easy to implement and has...

Computational Modeling of Turbulent Spray Combustion

The objective of the research presented in this thesis is development and validation of predictive models or modeling approaches of liquid fuel combustion (spray combustion) in hot-diluted environments, known as flameless combustion or MILD combustion. The goal is to combine good physical insight, appropriate numerical methods and good software...

Transported PDF Modeling of Ethanol Spray in Hot-Diluted Coflow Flame

This paper presents a numerical modeling study of one ethanol spray flame from the Delft Spray-in-Hot-Coflow (DSHC) database, which has been used to study Moderate or Intense Low-oxygen Dilution (MILD) combustion of liquid fuels (Correia Rodrigues et al. Combust. Flame 162(3), 759–773, 2015). A “Lagrangian-Lagrangian” approach is adopted where...

Spray combustion in moderate and intense low-oxygen conditions: An experimental study

Nitric oxides (NOx) are formed as a byproduct of combustion and contribute to ground-level ozone formation and the creation of conditions harmful for human health. In response to air pollutant emissions regulations, technologies for controlling NOx formation for a entire spectrum of fuels ranging from gaseous, liquid, coals, biomass and residue...

Modeling ethanol spray jet flame in hot-diluted coflow with transported PDF

MILD Combustion, also known as flameless combustion, is attracting wide scientific interest due to its potential of high efficiency and low NOx emission. This paper focuses on the numerical modeling of one of the ethanol spray flame cases from the Delft Spray-in-Hot-Coflow (DSHC) burner, which has been used to study MILD oxidation of liquid...

Numerical Simulation of Delft-Jet-in-Hot-Coflow (DJHC) Flames Using the Eddy Dissipation Concept Model for Turbulence–Chemistry Interaction

In this paper, we report results of a numerical investigation of turbulent natural gas combustion for a jet in a coflow of lean combustion products in the Delft-Jet-in-Hot-Coflow (DJHC) burner which emulates MILD (Moderate and Intense Low Oxygen Dilution) combustion behavior. The focus is on assessing the performance of the Eddy Dissipation...