Combined experimental and numerical study of ethanol laminar flame extinction

This study investigates the increase in methane and biogas flame reactivity enabled by the addition of syngas produced through fuel reforming. To isolate thermodynamic and chemical effects on the reactivity of the mixture, the burner simulations are performed with a constant adiabatic flame temperature of 1800 K. Compositions and temperatures are calculated with the chemical equilibrium solver of CANTERA® and the reactivity of the mixture is quantified using the adiabatic, freely-propagating premixed flame, and perfectly-stirred reactors of the CHEMKIN-Pro® software package. The results show that the produced syngas has a content of up to 30 % H2 with a temperature up to 950 K. When added to the fuel, it increases the laminar flame speed while maintaining a burning temperature of 1800 K. Even when cooled to 300 K, the laminar flame speed increases up to 30 % from the baseline of pure biogas. Hence, a system can be developed that controls and improves biogas flame stability under low reactivity conditions by varying the fraction of added syngas to the mixture. This motivates future experimental work on reforming technologies coupled with gas turbine exhausts to validate this numerical work.

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An experimental and numerical study of stagnation point heat transfer for methane/air laminar flame impinging on a flat surface

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2007.10.018 ◽

2008 ◽

Vol 51 (13-14) ◽

pp. 3595-3607 ◽

Cited By ~ 28

Author(s):

Subhash Chander ◽

Anjan Ray

Keyword(s):

Heat Transfer ◽

Stagnation Point ◽

Flat Surface ◽

Laminar Flame ◽

Numerical Study

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A Numerical Study on the Influence of Hydrogen Addition on Soot Formation in a Laminar Aviation Kerosene (Jet A1) Flame at Elevated Pressure

10.1115/gt2021-59203 ◽

2021 ◽

Author(s):

Mingshan Sun ◽

Zhiwen Gan

Keyword(s):

Volume Fraction ◽

Soot Formation ◽

Laminar Flame ◽

Numerical Study ◽

Soot Volume Fraction ◽

Elevated Pressure ◽

Condensation Process ◽

Hydrogen Addition ◽

Aviation Kerosene ◽

Soot Precursor

Abstract The hydrogen addition is a potential way to reduce the soot emission of aviation kerosene. The current study analyzed the effect of hydrogen addition on aviation kerosene (Jet A1) soot formation in a laminar flame at elevated pressure to obtain a fundamental understanding of the reduced soot formation by hydrogen addition. The soot formation of flame was simulated by CoFlame code. The soot formation of kerosene-nitrogen-air, (kerosene + replaced hydrogen addition)-nitrogen-air, (kerosene + direct hydrogen addition)-nitrogen-air and (kerosene + direct nitrogen addition)-nitrogen-air laminar flames were simulated. The calculated pressure includes 1, 2 and 5 atm. The hydrogen addition increases the peak temperature of Jet A1 flame and extends the height of flame. The hydrogen addition suppresses the soot precursor formation of Jet A1 by physical dilution effect and chemical inhibition effect, which weaken the poly-aromatic hydrocarbon (PAH) condensation process and reduce the soot formation. The elevated pressure significantly accelerates the soot precursor formation and increases the soot formation in flame. Meanwhile, the ratio of reduced soot volume fraction to base soot volume fraction by hydrogen addition decreases with the increase of pressure, indicating that the elevated pressure weakens the suppression effect of hydrogen addition on soot formation in Jet A1 flame.

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Numerical study of laminar flame properties of diluted methane-hydrogen-air flames at high pressure and temperature using detailed chemistry

International Journal of Hydrogen Energy ◽

10.1016/j.ijhydene.2011.06.053 ◽

2011 ◽

Vol 36 (18) ◽

pp. 12035-12047 ◽

Cited By ~ 51

Author(s):

Sabre Bougrine ◽

Stéphane Richard ◽

André Nicolle ◽

Denis Veynante

Keyword(s):

High Pressure ◽

Laminar Flame ◽

Numerical Study ◽

High Pressure And Temperature ◽

Detailed Chemistry

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Numerical Study on the Effect of Real Syngas Compositions on Ignition Delay Times and Laminar Flame Speeds at Gas Turbine Conditions

Volume 1B: Combustion, Fuels and Emissions ◽

10.1115/gt2013-95156 ◽

2013 ◽

Cited By ~ 1

Author(s):

Olivier Mathieu ◽

Eric L. Petersen ◽

Alexander Heufer ◽

Nicola Donohoe ◽

Wayne Metcalfe ◽

...

Keyword(s):

Ignition Delay ◽

Delay Time ◽

Gas Turbines ◽

Ignition Delay Time ◽

Laminar Flame ◽

Numerical Study ◽

Fuel Mixture ◽

Flame Speed ◽

Operating Conditions ◽

Combustion Properties

Depending on the feedstock and the production method, the composition of syngas can include (in addition to H2 and CO) small hydrocarbons, diluents (CO2, water, and N2), and impurities (H2S, NH3, NOx, etc.). Despite this fact, most of the studies on syngas combustion do not include hydrocarbons or impurities and in some cases not even diluents in the fuel mixture composition. Hence, studies with realistic syngas composition are necessary to help designing gas turbines. The aim of this work was to investigate numerically the effect of the variation in the syngas composition on some fundamental combustion properties of premixed systems such as laminar flame speed and ignition delay time at realistic engine operating conditions. Several pressures, temperatures, and equivalence ratios were investigated. To perform this parametric study, a state-of-the-art C0-C5 detailed kinetics mechanism was used. Results of this study showed that the addition of hydrocarbons generally reduces the reactivity of the mixture (longer ignition delay time, slower flame speed) due to chemical kinetic effects. The amplitude of this effect is however dependent on the nature and concentration of the hydrocarbon as well as the initial condition (pressure, temperature, and equivalence ratio).

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