Correction to: On the Flame Shape in a Premixed Swirl Stabilised Burner and its Dependence on the Laminar Flame Speed

AbstractGas turbines for power generation are optimised to run with fossil fuels but as a response to tighter pollutant regulations and to enable the use of renewable fuels there is a great interest in improving fuel flexibility. One interesting renewable fuel is syngas from biomass gasification but its properties vary depending on the feedstock and gasification principle, and are significantly different from conventional fuels. This paper aims to give an overview of the differences in combustion behaviour by comparing numerical solutions with methane and several different synthesis gas compositions. The TECFLAM swirl burner geometry, which is designed to be representative of common gas turbine burners, was selected for comparison. The advantage with this geometry is that detailed experimental measurements with methane are publicly available. A two-stage approach was employed with development and validation of an advanced CFD model against experimental data for methane combustion followed by simulations with four syngas mixtures. The validated model was used to compare the flame shape and other characteristics of the flow between methane, 40% hydrogen enriched methane and four typical syngas compositions. It was found that the syngas cases experience lower swirl intensity due to high axial velocities that weakens the inner recirculation zone. Moreover, the higher laminar flame speed of the syngas cases has a strong effect on the flame front shape by bending it away from the axial direction, by making it shorter and by increasing the curvature of the flame front. A hypothesis that the flame shape and position is primarily governed by the laminar flame speed is supported by the almost identical flame shapes for bark powder syngas and 40% hydrogen enriched methane. These gas mixtures have almost identical laminar flame speeds for the relevant equivalence ratios but the heating value of the syngas is more than a factor of 3 smaller than that of the hydrogen enriched methane. The syngas compositions used are representative of practical gasification processes and biomass feedstocks. The demonstrated strong correlation between laminar flame speed and flame shape could be used as a rule of thumb to quickly judge whether the flame might come in contact with the structure or in other ways be detrimental to the function of the combustion system.

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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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An experimental and reduced modeling study of the laminar flame speed of jet fuel surrogate components

Fuel ◽

10.1016/j.fuel.2013.05.105 ◽

2013 ◽

Vol 113 ◽

pp. 586-597 ◽

Cited By ~ 26

Author(s):

J.D. Munzar ◽

B. Akih-Kumgeh ◽

B.M. Denman ◽

A. Zia ◽

J.M. Bergthorson

Keyword(s):

Laminar Flame ◽

Jet Fuel ◽

Flame Speed ◽

Laminar Flame Speed ◽

Reduced Modeling ◽

Fuel Surrogate ◽

Modeling Study

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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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