Measurement of Laminar Flame Speed and Chemical Kinetic Model of 1-Pentene/Air Mixtures

New Laminar Flame Speed measurements have been taken for a wide range of syngas mixtures containing hydrocarbon impurities. These experiments began with two baseline syngas mixtures. The first of these baseline mixtures was a bio-syngas with a 50/50 H2/CO split, and the second baseline mixture was a coal syngas with a 40/60 H2/CO split. Experiments were conducted over a range of equivalence ratios from ϕ = 0.5 to 3 at initial conditions of 1 atm and 300 K. Upon completion of the baseline experiments, two different hydrocarbons were added to the fuel mixtures at levels ranging from 0.8 to 15% by volume, keeping the H2/CO ratio locked for the bio-syngas and coal syngas mixtures. The addition of these light hydrocarbons, namely CH4 and C2H6, had been shown in recent calculations by the authors to have significant impacts on the laminar flame speed, and the present experiments validated the suspected trends. For example, a 7% addition of methane to the coal-syngas blend decreased the peak flame speed by about 25% and shifted it from ϕ = 2.2 to a leaner value near ϕ = 1.5. Also, the addition of ethane at 1.7% reduced the mixture flame speed more than a similar addition of methane (1.6%). In general, the authors’ chemical kinetic model over predicted the laminar flame speed by about 10–20% for the mixtures containing the hydrocarbons. The decrease in laminar flame speed with the addition of the hydrocarbons can be explained by the increased importance of the inhibiting reaction CH3 + H (+M) ↔ CH4 (+M), which also explains the enhanced effect of C2H6 compared to CH4, where the former produces more CH3 radicals, particularly at fuel rich conditions.

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H Radical Sensitivity-Assisted Automatic Chemical Kinetic Model Reduction for Laminar Flame Chemistry Retaining: A Case Study of Gasoline–DME Mixture under Engine Conditions

Energy & Fuels ◽

10.1021/acs.energyfuels.8b04282 ◽

2019 ◽

Vol 33 (4) ◽

pp. 3551-3556 ◽

Cited By ~ 7

Author(s):

Yulin Chen ◽

Tao Chen ◽

Yifang Feng ◽

Je Ir Ryu ◽

Huan Yang ◽

...

Keyword(s):

Kinetic Model ◽

Model Reduction ◽

Laminar Flame ◽

Chemical Kinetic ◽

Chemical Kinetic Model ◽

Flame Chemistry

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Development of a chemical-kinetic database for the laminar flame speed under GDI and water injection engine conditions

Energy Procedia ◽

10.1016/j.egypro.2018.08.043 ◽

2018 ◽

Vol 148 ◽

pp. 154-161 ◽

Cited By ~ 5

Author(s):

Giulio Cazzoli ◽

Stefania Falfari ◽

Gian Marco Bianchi ◽

Claudio Forte

Keyword(s):

Laminar Flame ◽

Water Injection ◽

Chemical Kinetic ◽

Flame Speed ◽

Laminar Flame Speed

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Chemical Kinetic Model Reduction and Analysis of Tetrahydrofuran Combustion Using Stochastic Species Elimination

ASME 2020 Power Conference ◽

10.1115/power2020-16583 ◽

2020 ◽

Author(s):

Mazen A. Eldeeb ◽

Malshana Wadugurunnehalage

Keyword(s):

Kinetic Model ◽

Model Reduction ◽

Ignition Delay ◽

Delay Time ◽

Ignition Delay Time ◽

Laminar Flame ◽

Chemical Kinetic ◽

Reduced Model ◽

Chemical Kinetic Model ◽

Parameter Modification

Abstract In this work, a chemical kinetic modeling study of the high-temperature ignition and laminar flame behavior of Tetrahydrofuran (THF), a promising second-generation transportation biofuel, is presented. Stochastic Species Elimination (SSE) model reduction approach (Eldeeb and Akih-Kumgeh, Proceedings of ASME Power Conference 2018) is implemented to develop multiple skeletal versions of a detailed chemical kinetic model of THF (Fenard et al., Combustion and Flame, 2018) based on ignition delay time simulations at various pressures and temperature ranges. The detailed THF model contains 467 species and 2390 reactions. The developed skeletal versions are combined into an overall reduced model of THF, consisting of 193 species and 1151 reactions. Ignition delay time simulations are performed using detailed and reduced models, with varying levels of agreement observed at most conditions. Sensitivity analysis is then performed to identify the most important reactions responsible for the observed performance of the reduced model. Reaction rate parameter modification is performed for such reactions in order to improve the agreement of detailed and reduced model predictions with literature experimental ignition data. The work contributes toward improved understanding and modeling of the oxidation kinetics of potential transportation biofuels, especially cyclic ethers.

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Experimental study on laminar flame speeds and chemical kinetic model of 2,4,4-trimethyl-1-pentene

Fuel ◽

10.1016/j.fuel.2018.05.011 ◽

2018 ◽

Vol 229 ◽

pp. 95-104 ◽

Cited By ~ 3

Author(s):

Dong Zheng ◽

Bei-Jing Zhong ◽

Peng-Fei Xiong

Keyword(s):

Experimental Study ◽

Kinetic Model ◽

Laminar Flame ◽

Chemical Kinetic ◽

Chemical Kinetic Model

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A Chemical-Kinetic Approach to the Definition of the Laminar Flame Speed for the Simulation of the Combustion of Spark-Ignition Engines

10.4271/2017-24-0035 ◽

2017 ◽

Cited By ~ 5

Author(s):

Giulio Cazzoli ◽

Claudio Forte ◽

Gian Marco Bianchi ◽

Stefania Falfari ◽

Sergio Negro

Keyword(s):

Laminar Flame ◽

Spark Ignition ◽

Chemical Kinetic ◽

Flame Speed ◽

Kinetic Approach ◽

Laminar Flame Speed ◽

Spark Ignition Engines ◽

Definition Of

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Laminar and Turbulent Flame Speeds for Natural Gas/Hydrogen Blends

Volume 4B: Combustion, Fuels and Emissions ◽

10.1115/gt2014-26742 ◽

2014 ◽

Author(s):

A. Morones ◽

S. Ravi ◽

D. Plichta ◽

E. L. Petersen ◽

N. Donohoe ◽

...

Keyword(s):

Natural Gas ◽

Laminar Flame ◽

Turbulent Flame ◽

Initial Pressure ◽

Chemical Kinetic ◽

Flame Speed ◽

Intensity Level ◽

Chemical Kinetic Model ◽

Turbulent Flame Speed ◽

Reaction Zones

Hydrogen-based fuels have become a primary interest in the gas turbine market. To better predict the reactivity of mixtures containing different levels of hydrogen, laminar and turbulent flame speed experiments have been conducted. The laminar flame speed measurements were performed for various methane and natural gas surrogate blends with significant amounts of hydrogen at elevated pressures (up to 5 atm) and temperatures (up to 450 K) using a heated, high-pressure, cylindrical, constant-volume vessel. The hydrogen content ranged from 50% to 90% by volume. All measurements were compared to a chemical kinetic model, and good agreement within experimental measurement uncertainty was observed over most conditions. Turbulent combustion experiments were also performed for pure H2 and 50:50 H2:CH4 mixtures using a fan-stirred flame speed vessel. All tests were made with a fixed integral length scale of 27 mm and with a turbulent intensity level of 1.5 m/s at 1 atm initial pressure. Most of the turbulent flame speed results were in either the corrugated or thin reaction zones when plotted on a Borghi diagram, with Damköhler numbers up to 100 and turbulent Reynolds numbers between about 100 and 450. Flame speeds for a 50:50 blend of H2:CH4 for both laminar and turbulent cases were about a factor of 1.8 higher than for pure methane.

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Experimental Investigation of Laminar Flame Speeds for Medium Calorific Gas With Various Amounts of Hydrogen and Carbon Monoxide Content at Gas Turbine Temperatures

Volume 2: Combustion, Fuels and Emissions, Parts A and B ◽

10.1115/gt2010-22275 ◽

2010 ◽

Cited By ~ 3

Author(s):

Ivan R. Sigfrid ◽

Ronald Whiddon ◽

Robert Collin ◽

Jens Klingmann

Keyword(s):

Gas Turbine ◽

Equivalence Ratio ◽

Room Temperature ◽

Laminar Flame ◽

Chemical Kinetic ◽

Flame Speed ◽

Laminar Flame Speed ◽

Kinetic Mechanisms ◽

Group A ◽

Group B

It is expected that, in the future, gas turbines will be operated on gaseous fuels currently unutilized. The ability to predict the range of feasible fuels, and the extent to which existing turbines must be modified to accommodate these fuels, rests on the nature of these fuels in the combustion environment. Understanding the combustion behavior is aided by investigation of syngases of similar composition. As part of an ongoing project at the Lund University Departments of Thermal Power Engineering and Combustion Physics, to investigate syngases in gas turbine combustion, the laminar flame speed of five syngases (see table) have been measured. The syngases examined are of two groups. The first gas group (A), contains blends of H2, CO and CH4, with high hydrogen content. The group A gases exhibit a maximum flame speed at an equivalence ratio of approximately 1.4, and a flame speed roughly four times that of methane. The second gas group (B) contains mixtures of CH4 and H2 diluted with CO2. Group B gases exhibit maximum flame speed at an equivalence ratio of 1, and flame speeds about 3/4 that of methane. A long tube Bunsen-type burner was used and the conical flame was visualized by Schlieren imaging. The flame speeds were measured for a range of equivalence ratios using a constrained cone half-angle method. The equivalence ratio for measurements ranged from stable lean combustion to rich combustion for room temperature (25°C) and an elevated temperature representative of a gas turbine at full load (270°C). The experimental procedure was verified by methane laminar flame speed measurement; and, experimental results were compared against numerical simulations based on GRI 3.0, Hoyerman and San Diego chemical kinetic mechanisms using the DARS v2.02 combustion modeler. On examination, all measured laminar flame speeds at room temperature were higher than values predicted by the aforementioned chemical kinetic mechanisms, with the exception of group A gases, which were lower than predicted.

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