Combustion behavior of single iron particles-part I: An experimental study in a drop-tube furnace under high heating rates and high temperatures

Panahi, Aidin; Chen, Di; Schiemann, Martin; Fujinawa, Aki; Mi, Xiaocheng; Bergthorson, Jeffrey M.; Levendis, Yiannis A.

doi:10.1016/j.jaecs.2022.100097

Cited by 11 publications

(8 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Mi et al (2022) proposed an alternative iron combustion model that describes the growth of iron oxide layers consisting of FeO and Fe 3 O 4 by a parabolic rate law. Over the last couple of years, the step from single particle investigations (Ning et al 2021Fujinawa et al 2023;Panahi et al 2023;Ning et al 2023) to the study of metal particle clouds in laminar flows has received a substantial boost both numerically and experimentally. The experimental investigations mainly focus on the stabilisation and quantification of laminar burning velocities and on identifying different combustion regimes (Tang et al 2009;Tang et al 2011;Julien et al 2015;Wright et al 2016;McRae et al 2019;Palečka et al 2019;Poletaev and Khlebnikova 2022;Fedoryk et al 2023).…”

Section: Introductionmentioning

confidence: 99%

Carrier-Phase DNS of Ignition and Combustion of Iron Particles in a Turbulent Mixing Layer

Luu,

Shamooni,

Kronenburg

et al. 2024

Flow Turbulence Combust

View full text Add to dashboard Cite

Three-dimensional carrier-phase direct numerical simulations (CP-DNS) of reacting iron particle dust clouds in a turbulent mixing layer are conducted. The simulation approach considers the Eulerian transport equations for the reacting gas phase and resolves all scales of turbulence, whereas the particle boundary layers are modelled employing the Lagrangian point-particle framework for the dispersed phase. The CP-DNS employs an existing sub-model for iron particle combustion that considers the oxidation of iron to FeO and that accounts for both diffusion- and kinetically-limited combustion. At first, the particle sub-model is validated against experimental results for single iron particle combustion considering various particle diameters and ambient oxygen concentrations. Subsequently, the CP-DNS approach is employed to predict iron particle cloud ignition and combustion in a turbulent mixing layer. The upper stream of the mixing layer is initialised with cold particles in air, while the lower stream consists of hot air flowing in the opposite direction. Simulation results show that turbulent mixing induces heating, ignition and combustion of the iron particles. Significant increases in gas temperature and oxygen consumption occur mainly in regions where clusters of iron particles are formed. Over the course of the oxidation, the particles are subjected to different rate-limiting processes. While initially particle oxidation is kinetically-limited it becomes diffusion-limited for higher particle temperatures and peak particle temperatures are observed near the fully-oxidised particle state. Comparing the present non-volatile iron dust flames to general trends in volatile-containing solid fuel flames, non-vanishing particles at late simulation times and a stronger limiting effect of the local oxygen concentration on particle conversion is found for the present iron dust flames in shear-driven turbulence.

show abstract

Section: Introductionmentioning

confidence: 99%

Carrier-Phase DNS of Ignition and Combustion of Iron Particles in a Turbulent Mixing Layer

Luu,

Shamooni,

Kronenburg

et al. 2024

Flow Turbulence Combust

View full text Add to dashboard Cite

show abstract

“…To design and improve real-world iron-fuel burners, an in-depth understanding of the fundamentals underlying the combustion of single iron particles is required. In the past few years, the number of more detailed experimental − and theoretical studies − regarding the combustion of single iron particles has increased drastically. In this early research on iron particle combustion, a good agreement between experiments and theoretical models for low gas temperature (300 K) and low oxygen concentration cases (up to X O2 = 0.21) was obtained.…”

Section: Introductionmentioning

confidence: 99%

Effect of Fe–O ReaxFF on Liquid Iron Oxide Properties Derived from Reactive Molecular Dynamics

Thijs,

Kritikos,

Giusti

et al. 2023

J. Phys. Chem. A

Self Cite

View full text Add to dashboard Cite

As iron powder nowadays attracts research attention as a carbon-free, circular energy carrier, molecular dynamics (MD) simulations can be used to better understand the mechanisms of liquid iron oxidation at elevated temperatures. However, prudence must be practiced in the selection of a reactive force field. This work investigates the influence of currently available reactive force fields (ReaxFFs) on a number of properties of the liquid iron–oxygen (Fe–O) system derived (or resulting) from MD simulations. Liquid Fe–O systems are considered over a range of oxidation degrees Z O , which represents the molar ratio of O/(O + Fe), with 0 < Z O < 0.6 and at a constant temperature of 2000 K, which is representative of the combustion temperature of micrometric iron particles burning in air. The investigated properties include the minimum energy path, system structure, (im)miscibility, transport properties, and the mass and thermal accommodation coefficients. The properties are compared to experimental values and thermodynamic calculation results if available. Results show that there are significant differences in the properties obtained with MD using the various ReaxFF parameter sets. Based on the available experimental data and equilibrium calculation results, an improved ReaxFF is required to better capture the properties of a liquid Fe–O system.

show abstract

“…The furnace wall temperature was maintained at 1400 K and the gas temperature at the furnace centerline was measured with radiation-corrected thermocouples to be ~1350 K for a large portion of the length of the 25 cm long radiation zone [77]. The heating rate of the particles was determined to be in the range of 10 4 -10 5 K/s; more details are given in Refs [34,68].…”

Section: Experimental Apparatus and Proceduresmentioning

confidence: 99%

“…The pyrometric signal ratio method was used to calculate three temperatures based on particle radiation intensity signals obtained from three wavelength ratios (S999/S810, S810/S640, S999/S640) and accounting for the efficiencies of all the pyrometer components. The details of the method and pyrometer's calibration were documented in [17,34,45].…”

Section: Three-color Pyrometer and Calibrationmentioning

confidence: 99%

See 1 more Smart Citation

On the combustion parameters of coal, biomass and iron, burning either as isolated particles or in groups of particles

Yao

View full text Add to dashboard Cite

In this research, combustion characteristics of pulverized solid fuels, including bituminous coal, various biomass types, and iron, were investigated with experimental methods. Emphasis was placed on obtaining radiative parameters for these fuels, including spectral emissivity, temperature and soot volume fractions. Moreover, the structural development of the chars of bituminous coal and various biomass samples, upon devolatilization, was studied by using experimental data and a numerical model. Such measurements can be used in the development of predictive numerical models for the operation and emissions of furnaces. The experimental methods that were used in this study included three-color pyrometry, spectrometry and highspeed cinematography. The following results were obtained: (i) For single particle combustion of coal and three types of biomasses, all three experimental methods were used to measure the combustion temperatures, spectral emissivities and soot volume fractions. The spectral emissivities of the chars volatile matter flames those fuels were measured, and average peak temperatures and 2D temperature distribution were identified. (ii) For group particles combustion of coal and biomasses, the spectrometer and high-speed camera were used to measure the combustion temperatures, spectral emissivities and soot volume fractions. Average spectral emissivities and mean particle cloud temperatures were measured for two different particle number densities (PNDs) of these fuels in the furnace. (iii) For iron combustion, all three experimental methods were used to measure the combustion temperatures and spectral emissivities for single particle combustion and only the spectrometer and high-speed camera for group combustion. Average spectral emissivities of single particles for different oxygen concentration and groups of iron particles burning in air at different PNDs were measured. Corresponding average temperatures and 2D temperature distribution of single particles and groups combustion of iron were also measured. (iv) The numerical model, which was used in this work, is a kinetic model that was designed for char combustion of biomass which requires an experimental temperature profile. The model was used to determine the size and overall porosity (pore volume) of carbonaceous chars, originating from high-heating rates and hightemperature pyrolysis and/or combustion of biomass. The average char porosities (effective porosities) of several raw and torrefied biomass particles were calculated to be in the range of 92-95%. The average initial dimension of the chars, upon rapid pyrolysis, was in the range of 50-60% mid-value of the mesh size of the sieves used to size-classify their highly irregular parent biomass particles. Finally, this dissertation presents measurements and calculations of multiple critical combustion parameters for different fuels. It provides important information and lays the foundation for subsequent experimental research and applications for those renewable fuels. The combination of spect...

show abstract

Combustion behavior of single iron particles-part I: An experimental study in a drop-tube furnace under high heating rates and high temperatures

Cited by 11 publications

References 40 publications

Carrier-Phase DNS of Ignition and Combustion of Iron Particles in a Turbulent Mixing Layer

Carrier-Phase DNS of Ignition and Combustion of Iron Particles in a Turbulent Mixing Layer

Effect of Fe–O ReaxFF on Liquid Iron Oxide Properties Derived from Reactive Molecular Dynamics

On the combustion parameters of coal, biomass and iron, burning either as isolated particles or in groups of particles

Contact Info

Product

Resources

About