Journal ArticleDOI
Structure of turbulent non-premixed jet flames in a diluted hot coflow
Bassam B. Dally,Adonios N. Karpetis,Robert S. Barlow +2 more
- Vol. 29, Iss: 1, pp 1147-1154
TLDR
In this article, an experimental burner is used to simulate the heat and exhaust gas recirculation applied to a simple jet in a hot coflow, and the results show substantial variation in the flame structure and appearance with the decrease of the oxygen level.Abstract:
Moderate and intense low oxygen dilution combustion is a newly implemented and developed concept to achieve high thermal efficiency and fuel savings while maintaining emission of pollutants at very low levels. It utilizes the concept of heat and exhaust gas recirculation to achieve combustion at a reduced temperature, a flat thermal field, and low turbulence fluctuations. An experimental burner is used in this study to simulate the heat and exhaust gas recirculation applied to a simple jet in a hot coflow. Temporally and spatially resolved measurements of reactive scalars are conducted on three different turbulent nonpremixed flames of a H2/CH4 fuel mixture at a fixed-jet Reynolds number, and different oxygen levels in the hot oxidant stream. The data were collected using the single-point Raman-Rayleigh-laser-induced fluorescence technique. The results show substantial variation in the flame structure and appearance with the decrease of the oxygen level. By reducing the oxygen level in the hot coflow, the flame becomes less luminous, the temperature increase in the reaction zone can get as low as 100 K, and the levels of CO and OH are substantially lowered. The levels of NO also decrease with decreasing the oxygen levels and at 3% by mass, it is less that 5 ppm. For this case, a widely distributed NO profile is found which is not consistent with profiles for other oxygen levels.read more
Citations
More filters
Journal ArticleDOI
Review on ammonia as a potential fuel: from synthesis to economics
Agustin Valera-Medina,F. Amer-Hatem,Abul Kalam Azad,Irene C Dedoussi,M. de Joannon,Ravi Fernandes,Peter Glarborg,Hamid Hashemi,Xiaoyu He,Syed Mashruk,Jon G. McGowan,C. Mounaim-Rouselle,A. Ortiz-Prado,A. Ortiz-Valera,Ilenia Rossetti,Bo Shu,M. A. Yehia,Hua Xiao,Mário Costa +18 more
TL;DR: Ammonia has been considered as a candidate to power transport, produce energy, and support heating applications for decades, however, the particular characteristics of the molecule always made it a chemical with low, if any, benefit once compared to conventional fossil fuels as discussed by the authors.
Journal ArticleDOI
Simultaneous imaging of OH, formaldehyde, and temperature of turbulent nonpremixed jet flames in a heated and diluted coflow
TL;DR: In this paper, the spatial distribution of the hydroxyl radical (OH), formaldehyde (H2CO), and temperature, imaged using planar laser-induced fluorescence and Rayleigh scattering laser diagnostic techniques, are measured and presented.
Journal ArticleDOI
Ignition kernel formation and lift-off behaviour of jet-in-hot-coflow flames
TL;DR: In this paper, the stabilisation region of turbulent non-premixed flames of natural gas mixtures burning in a hot and diluted coflow was studied by recording the flame luminescence with an intensified high-speed camera.
Journal ArticleDOI
Numerical Simulation of Delft-Jet-in-Hot-Coflow (DJHC) Flames Using the Eddy Dissipation Concept Model for Turbulence–Chemistry Interaction
TL;DR: In this paper, the performance of the Eddy Dissipation Concept (EDC) model in combination with two-equation turbulence models and chemical kinetic schemes for about 20 species (Correa mechanism and DRM19 mechanism) was compared with experimental measurements.
Journal ArticleDOI
LES flamelet modeling of a three-stream MILD combustor: Analysis of flame sensitivity to scalar inflow conditions
Matthias Ihme,Yee Chee See +1 more
TL;DR: In this paper, a large-eddy simulation of a jet issuing into a hot and diluted coflow is performed, where a flamelet/progress variable (FPV) formulation is extended by introducing an additional conserved scalar associated with the oxidizer split.
References
More filters
Journal ArticleDOI
Flameless oxidation to reduce thermal no-formation
TL;DR: In this article, a special form of combustion, called flameless oxidation, is presented, where temperature peaks can be avoided at flameless oxidations, and thermal NO-formation is largely suppressed, even at very high air preheat temperatures.
Journal ArticleDOI
On reduced mechanisms for methaneair combustion in nonpremixed flames
TL;DR: In this article, a four-step mechanism for the combustion of methane in air in non-premixed flames is obtained by making steady-state and partial equilibrium approximations for minor species.
Journal ArticleDOI
The science and technology of combustion in highly preheated air
TL;DR: In this article, the possibility of low nitric oxide emission from highly preheated air combustion is intensively discussed, with the aim of maximizing the energy saving brought by a high rate of heat recirculation in generic industrial furnances.
Journal ArticleDOI
The structure of turbulent nonpremixed flames revealed by Raman-Rayleigh-LIF measurements
TL;DR: In this paper, a review of recent advances in understanding of the structure of turbulent non-premixed flames due to extensive data acquired from single-point and planar imaging experiments using the Raman, Rayleigh, and LIF diagnostic methods is presented.
Journal ArticleDOI
Laseroptical investigation of highly preheated combustion with strong exhaust gas recirculation
TL;DR: In this paper, laser-optical measurements using OH laser-induced predissociative fluorescence and Rayleigh thermometry were carried out in a combustion chamber with highly preheated air and strong exhaust gas recirculation.
Related Papers (5)
Modeling turbulent reacting jets issuing into a hot and diluted coflow
Farid Christo,Bassam B. Dally +1 more