Experimental and modeling study of laminar flame speed and non-premixed counterflow ignition of n-heptane

Currently, new concepts for power generation are discussed, as a response to combat global warming due to CO2 emissions stemming from the combustion of fossil fuels. These concepts include new, low-carbon fuels as well as centralized and decentralized solutions. Thus, a more diverse range of fuel supplies will be used, with (biogenic) low-caloric gases such as syngas and coke oven gas (COG) among them. Typical for theses low-caloric gases is the amount of hydrogen, with a share of 50% and even higher. However, hydrogen mixtures have a higher reactivity than natural gas (NG) mixtures, burned mostly in today's gas turbine combustors. Therefore, in the present work, a combined experimental and modeling study of nitrogen-enriched hydrogen–air mixtures, some of them with a share of methane, to be representative for COG, will be discussed focusing on laminar flame speed data as one of the major combustion properties. Measurements were performed in a burner test rig at ambient pressure and at a preheat temperature T0 of 373 K. Flames were stabilized at fuel–air ratios between about φ = 0.5–2.0 depending on the specific fuel–air mixture. This database was used for the validation of four chemical kinetic reaction models, including an in-house one, and by referring to hydrogen-enriched NG mixtures. The measured laminar flame speed data of nitrogen-enriched methane–hydrogen–air mixtures are much smaller than the ones of nitrogen-enriched hydrogen–air mixtures. The grade of agreement between measured and predicted data depends on the type of flames and the type of reaction model as well as of the fuel–air ratio: a good agreement was found in the fuel lean and slightly fuel-rich regime; a large underprediction of the measured data exists at very fuel-rich ratios (φ > 1.4). From the results of the present work, it is obvious that further investigations should focus on highly nitrogen-enriched methane–air mixtures, in particular for very high fuel–air ratio (φ > 1.4). This knowledge will contribute to a more efficient and a more reliable use of low-caloric gases for power generation.

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An experimental and modeling study of ammonia with enriched oxygen content and ammonia/hydrogen laminar flame speed at elevated pressure and temperature

Proceedings of the Combustion Institute ◽

10.1016/j.proci.2020.06.197 ◽

2020 ◽

Cited By ~ 1

Author(s):

Krishna Prasad Shrestha ◽

Charles Lhuillier ◽

Amanda Alves Barbosa ◽

Pierre Brequigny ◽

Francesco Contino ◽

...

Keyword(s):

Oxygen Content ◽

Laminar Flame ◽

Elevated Pressure ◽

Flame Speed ◽

Laminar Flame Speed ◽

Modeling Study

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Experimental and Kinetic Modeling Study of Laminar Flame Speed of Dimethoxymethane and Ammonia Blends

Energy & Fuels ◽

10.1021/acs.energyfuels.0c02269 ◽

2020 ◽

Vol 34 (11) ◽

pp. 14726-14740

Author(s):

Ayman M. Elbaz ◽

Binod Raj Giri ◽

Gani Issayev ◽

Krishna P. Shrestha ◽

Fabian Mauss ◽

...

Keyword(s):

Kinetic Modeling ◽

Laminar Flame ◽

Flame Speed ◽

Laminar Flame Speed ◽

Modeling Study

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The Influence of Diluent Gases on Combustion Properties of Natural Gas: A Combined Experimental and Modeling Study

Volume 3: Coal, Biomass and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration ◽

10.1115/gt2015-42752 ◽

2015 ◽

Cited By ~ 1

Author(s):

Jörn Ermel ◽

Sandra Richter ◽

Thomas Kick ◽

Marina Braun-Unkhoff ◽

Clemens Naumann ◽

...

Keyword(s):

Power Generation ◽

Natural Gas ◽

Laminar Flame ◽

Ambient Pressure ◽

Flame Speed ◽

Laminar Flame Speed ◽

Diverse Range ◽

Combustion Properties ◽

Modeling Study ◽

A Share

Currently, new concepts for power generation are discussed, as a response to combat global warming due to CO2 emissions stemming from the combustion of fossil fuels. These concepts include new, low-carbon fuels as well as centralized and decentralized solutions. Thus, a more diverse range of fuel supplies will be used, with (biogenic) low-caloric gases such as syngas and coke oven gas (COG) among them. Typical for theses low-caloric gases is the amount of hydrogen, with a share of 50% and even higher. However, hydrogen mixtures have a higher reactivity than natural gas (NG) mixtures, burned mostly in today’s gas turbine combustors. Therefore, in the present work, a combined experimental and modeling study of nitrogen-enriched hydrogen-air mixtures, some of them with a share of methane, to be representative for COG, will be discussed focusing on laminar flame speed data Su as one of the major combustion properties. Measurements were performed in a burner test rig at ambient pressure and at a preheat temperature T0 of 373 K. Flames were stabilized at fuel-air ratios between about φ = 0.5–2.1, depending on the specific fuel-air mixture. This database was used for the validation of four chemical kinetic reaction models, including an in-house one, and by referring to hydrogen-enriched natural gas mixtures. The measured laminar flame speed data of nitrogen-enriched methane-hydrogen-air mixtures are much smaller than the ones of nitrogen-enriched hydrogen-air mixtures. The grade of agreement between measured and predicted data depends on the type of flames and the type of reaction model as well as of the fuel-air ratio: good agreement was found in the fuel lean and slightly fuel rich regime; a large underprediction of the measured data exists at very fuel-rich ratios (φ > 1.4). From the results of the present work, it is obvious that further investigations should focus on highly nitrogen-enriched methane-air mixtures, in particular for very high fuel-air ratio (φ > 1.4). This knowledge will contribute to a more efficient and a more reliable use of low-caloric gases for power generation.

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An experimental and chemical kinetic modeling study of 1,3-butadiene combustion: Ignition delay time and laminar flame speed measurements

Combustion and Flame ◽

10.1016/j.combustflame.2018.08.006 ◽

2018 ◽

Vol 197 ◽

pp. 423-438 ◽

Cited By ~ 138

Author(s):

Chong-Wen Zhou ◽

Yang Li ◽

Ultan Burke ◽

Colin Banyon ◽

Kieran P. Somers ◽

...

Keyword(s):

Kinetic Modeling ◽

Ignition Delay ◽

Delay Time ◽

Ignition Delay Time ◽

Laminar Flame ◽

Chemical Kinetic ◽

Flame Speed ◽

Laminar Flame Speed ◽

Modeling Study

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A Numerical Study on the Reactivity of Biogas/Reformed-Gas/Air and Methane/Reformed-Gas/Air Mixtures at Gas Turbine Relevant Conditions

Volume 3: Coal, Biomass and Alternative Fuels; Cycle Innovations; Electric Power; Industrial and Cogeneration; Organic Rankine Cycle Power Systems ◽

10.1115/gt2016-56655 ◽

2016 ◽

Cited By ~ 3

Author(s):

Pablo Diaz Gomez Maqueo ◽

Philippe Versailles ◽

Gilles Bourque ◽

Jeffrey M. Bergthorson

Keyword(s):

Gas Turbine ◽

Laminar Flame ◽

Numerical Study ◽

Flame Temperature ◽

Flame Speed ◽

Flame Stability ◽

Laminar Flame Speed ◽

Fuel Reforming ◽

Numerical Work ◽

Chemical Effects

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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Laminar flame speed measurements of dimethyl ether in air at pressures up to 10atm

Fuel ◽

10.1016/j.fuel.2010.07.040 ◽

2011 ◽

Vol 90 (1) ◽

pp. 331-338 ◽

Cited By ~ 60

Author(s):

Jaap de Vries ◽

William B. Lowry ◽

Zeynep Serinyel ◽

Henry J. Curran ◽

Eric L. Petersen

Keyword(s):

Dimethyl Ether ◽

Laminar Flame ◽

Flame Speed ◽

Laminar Flame Speed

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Laminar flame speed correlations for methane, ethane, propane and their mixtures, and natural gas and gasoline for spark-ignition engine simulations

International Journal of Engine Research ◽

10.1177/1468087417720018 ◽

2017 ◽

Vol 18 (9) ◽

pp. 951-970 ◽

Cited By ~ 31

Author(s):

Riccardo Amirante ◽

Elia Distaso ◽

Paolo Tamburrano ◽

Rolf D Reitz

Keyword(s):

Natural Gas ◽

Laminar Flame ◽

Spark Ignition ◽

Flame Speed ◽

Operating Conditions ◽

Spark Ignition Engine ◽

Computational Time ◽

Laminar Flame Speed ◽

Spark Ignition Engines ◽

Empirical Correlations

The laminar flame speed plays an important role in spark-ignition engines, as well as in many other combustion applications, such as in designing burners and predicting explosions. For this reason, it has been object of extensive research. Analytical correlations that allow it to be calculated have been developed and are used in engine simulations. They are usually preferred to detailed chemical kinetic models for saving computational time. Therefore, an accurate as possible formulation for such expressions is needed for successful simulations. However, many previous empirical correlations have been based on a limited set of experimental measurements, which have been often carried out over a limited range of operating conditions. Thus, it can result in low accuracy and usability. In this study, measurements of laminar flame speeds obtained by several workers are collected, compared and critically analyzed with the aim to develop more accurate empirical correlations for laminar flame speeds as a function of equivalence ratio and unburned mixture temperature and pressure over a wide range of operating conditions, namely [Formula: see text], [Formula: see text] and [Formula: see text]. The purpose is to provide simple and workable expressions for modeling the laminar flame speed of practical fuels used in spark-ignition engines. Pure compounds, such as methane and propane and binary mixtures of methane/ethane and methane/propane, as well as more complex fuels including natural gas and gasoline, are considered. A comparison with available empirical correlations in the literature is also provided.

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