scholarly journals An Experimental and Kinetic Modelling Study on Laminar Premixed Flame Characteristics of Ethanol/Acetone Mixtures

Energies ◽  
2021 ◽  
Vol 14 (20) ◽  
pp. 6713
Author(s):  
Yangxun Liu ◽  
Weinan Liu ◽  
Huihong Liao ◽  
Wenhua Zhou ◽  
Cangsu Xu
Keyword(s):  
Sensitivity Analysis ◽  
Alternative Fuels ◽  
Reaction Pathway ◽  
Kinetic Modelling ◽  
Flame Structure ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Fuel Blends ◽  
Constant Volume Combustion Chamber ◽  
Pathway Analyses

Since both ethanol and acetone are the main components in many alternative fuels, research on the burning characteristics of ethanol-acetone blends is important to understand the combustion phenomena of these alternative fuels. In the present study, the burning characteristics of ethanol-acetone fuel blends are investigated at a temperature of 358 K and pressure of 0.1 MPa with equivalence ratios ranging from 0.7 to 1.4. Ethanol at 100% vol., 25% vol. ethanol/75% vol. acetone, 50% vol. ethanol/50% vol. acetone, 75% vol. ethanol/25% vol. acetone, and 100% vol. acetone are studied by the constant volume combustion chamber (CVCC) method. The results show that the laminar burning velocities of the fuel blends are between that of 100% vol. acetone and 100% vol. ethanol. As the ethanol content increases, the laminar burning velocities of the mixed fuels increase. Furthermore, a detailed chemical kinetic mechanism (AramcoMech 3.0) is used for simulating the burning characteristics of the mixtures. The directed relation graph (DRG), DRG with error propagation (DRGEP), sensitivity analysis (SA), and full species sensitivity analysis (FSSA) are used for mechanism reduction. The flame structure of the skeletal mechanism does not change significantly, and the concentration of each species remains basically the same value after the reaction. The numbers of reactions and species are reduced by 90% compared to the detailed mechanism. Sensitivity and reaction pathway analyses of the burning characteristics of the mixtures indicate that the reaction C2H2+H(+M)<=>C2H3(+M) is the key reaction.

scholarly journals Investigating the Effects of Chemical Mechanism on Soot Formation Under High-Pressure Fuel Pyrolysis

2021 ◽  
Vol 7 ◽  
Author(s):  
Nick J. Killingsworth ◽  
Tuan M. Nguyen ◽  
Carter Brown ◽  
Goutham Kukkadapu ◽  
Julien Manin
Keyword(s):  
High Pressure ◽  
Soot Formation ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Chemical Mechanism ◽  
Navier Stokes ◽  
Chemical Mechanisms ◽  
Constant Volume Combustion Chamber ◽  
Fuel Pyrolysis ◽  
Soot Model

We performed Computational Fluid Dynamics (CFD) simulations using a Reynolds-Averaged Navier-Stokes (RANS) turbulence model of high-pressure spray pyrolysis with a detailed chemical kinetic mechanism encompassing pyrolysis of n-dodecane and formation of polycyclic aromatic hydrocarbons. We compare the results using the detailed mechanism and those found using several different reduced chemical mechanisms to experiments carried out in an optically accessible, high-pressure, constant-volume combustion chamber. Three different soot models implemented in the CONVERGE CFD software are used: an empirical soot model, a method of moments, and a discrete sectional method. There is a large variation in the prediction of the soot between different combinations of chemical mechanisms and soot model. Furthermore, the amount of soot produced from all models is substantially less than experimental measurements. All of this indicates that there is still substantial work that needs to be done to arrive at simulations that can be relied on to accurately predict soot formation.

Chemical Kinetic Study on Reaction Pathway of Anisole Oxidation at Various Operating Condition

2020 ◽  
Author(s):  
Shrabanti Roy ◽  
Omid Askari
Keyword(s):  
Kinetic Study ◽  
Equivalence Ratio ◽  
Initial Conditions ◽  
Reaction Pathway ◽  
Chemical Kinetic ◽  
Chemical Mechanism ◽  
Experimental Result ◽  
Alternative Source ◽  
Stirred Reactor ◽  
Constant Volume Combustion Chamber

Abstract Biofuels are considered as an alternative source of energy which can decrease the growing consumption of fossil fuel, hence decreasing pollution. Anisole (methoxybenzene) is a potential source of biofuel produced from cellulose base compounds. It is mostly available as a surrogate of phenolic rich compound. Because of the attractive properties of this fuel in combustion, it is important to do detail kinetic study on oxidation of anisole. In this study a detail chemical mechanism is developed to capture the chemical kinetics of anisole oxidation. The mechanism is developed using an automatic reaction mechanism generator (RMG). To generate the mechanism, RMG uses some known set of species and initial conditions such as temperature, pressure, and mole fractions. Proper thermodynamic and reaction library is used to capture the aromaticity of anisole. The generated mechanism has 340 species and 2532 reactions. Laminar burning speed (LBS) calculated through constant volume combustion chamber (CVCC) at temperature ranges from 460–550 K, pressure of 2–3 atm and equivalence ratio of 0.8–1.4 is used to validate the generated mechanism. Some deviation with experimental result is observed with the newly generated mechanism. Important reaction responsible for LBS calculation, is selected through sensitivity analysis. Rate coefficient of sensitive reactions are collected from literature to modify and improve the mechanism with experimental result. The generated mechanism is further validated with available ignition delay time (IDT) results ranging from 10–20 atm pressure, 0.5–1 equivalence ratio and 870–1600 K temperature. A good agreement of results is observed at different operating ranges. Oxidation of anisole at stoichiometric condition and atmospheric pressure in jet stirred reactor is also used to compare the species concentration of the mechanism. This newly generated mechanism is considered as a good addition for further study of anisole kinetics.

Prediction of Premixed Laminar Flame Structure and Burning Velocity of Aviation Fuel-Air Mixtures

2001 ◽  
Author(s):  
A. G. Kyne ◽  
P. M. Patterson ◽  
M. Pourkashanian ◽  
C. W. Wilson ◽  
A. Williams
Keyword(s):  
Reaction Mechanism ◽  
Laminar Flame ◽  
Burning Velocity ◽  
Flame Structure ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Aviation Fuel ◽  
Measured Temperature ◽  
Premixed Laminar ◽  
Increasing Temperature

The structure of a rich burner stabilised kerosene/O2/N2 flame is predicted using a detailed chemical kinetic mechanism where the kerosene is represented by a mixture of n-decane and toluene. The chemical reaction mechanism, consisting of 440 reactions between 84 species, is capable of predicting the experimentally determined flame structure of Douté et al. (1995) with good success using the measured temperature profile as input. Sensitivity and reaction rate analyses are carried out to identify the most significant reactions and based on this the reaction mechanism was reduced to one with only 165 reactions without any loss of accuracy. Burning velocities of kerosene-air mixtures were also determined over an extensive range of equivalence ratios at atmospheric pressure. The initial temperature of the mixture was also varied and burning velocities were found to increase with increasing temperature. Burning velocities calculated using both the detailed and reduced mechanisms were essentially identical.

Reformed Fuel and Its Properties, Burning Speeds and Flame Characteristics

2005 ◽  
Author(s):  
Farzan Parsinejad ◽  
Edwin Shirk ◽  
Hameed Metghalchi
Keyword(s):  
Flame Propagation ◽  
Turbulent Flame ◽  
Flame Structure ◽  
Chemical Kinetic ◽  
Cylindrical Vessel ◽  
Flammability Limit ◽  
Lean Burn ◽  
Fuel Blend ◽  
Fuel Blends ◽  
Stable Flame

Premixed, lean burn combustion research has been focused for years on extending the lean flammability limit while maintaining both stable ignition and turbulent flame propagation. Burning speed is a fundamental physicochemical property of homogenous fuel/oxygen/diluent mixtures. It determines the rate of energy released during combustion and is of basic importance for developing and testing chemical kinetic models of hydrocarbons. The burning speed and flame structure of blends of reformed fuel and Methane-air mixtures have been studied using two similar constant volumes; a cylindrical vessel with end windows and a spherical chamber. The Experiments were conducted for a range of reformed fuel blends (20–80%) as well as mixture equivalence ratios (0.4–0.6). The burning speed results clearly define the regime of stable flame propagation for equivalence ratio/reformed fuel blend combinations.

An Experimental and Modeling Study Into Using Normal and Isocetane Fuel Blends as a Surrogate for a Hydroprocessed Renewable Diesel Fuel

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Jim Cowart ◽  
Michael Raynes ◽  
Len Hamilton ◽  
Dianne Luning Prak ◽  
Marco Mehl ◽  
...  
Keyword(s):  
Ignition Delay ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Renewable Diesel ◽  
Binary Blend ◽  
Combustion Modeling ◽  
Fuel Blends ◽  
Single Cylinder Engine ◽  
Engine Testing ◽  
Detailed Chemical

A new hydroprocessed renewable diesel (HRD) fuel comprised both straight chain and branched alkane fuel components. In an effort to find a research surrogate for this fuel, single cylinder engine testing was performed with various blends of n-hexadecane (cetane) and isocetane in order to find a binary surrogate mixture with similar performance characteristics to that of the HRD. A blend of approximately two-thirds n-hexadecane with one-third isocetane showed the most similar behavior based on conventional combustion metrics. Companion combustion modeling was then pursued using a combined detailed chemical kinetic mechanism for both n-hexadecane and isocetane. These modeling results show both the importance of isocetane in lengthening ignition delay (IGD), as well as the overall importance of chemical ignition delay as the dominating effect in the overall ignition delay of these binary blend fuels.

An Experimental and Modeling Study Into Using Normal and ISO Cetane Fuel Blends as a Surrogate for a Hydro-Processed Renewable Diesel (HRD) Fuel

2013 ◽  
Author(s):  
Jim Cowart ◽  
Michael Raynes ◽  
Len Hamilton ◽  
Dianne Luning Prak ◽  
Marco Mehl ◽  
...  
Keyword(s):  
Ignition Delay ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Renewable Diesel ◽  
Binary Blend ◽  
Combustion Modeling ◽  
Fuel Blends ◽  
Single Cylinder Engine ◽  
Engine Testing ◽  
Detailed Chemical

A new Hydro-processed Renewable Diesel (HRD) fuel is comprised of both straight chain and branched alkane fuel components. In an effort to find a research surrogate for this fuel, single cylinder engine testing was performed with various blends of n-hexadecane (cetane) and isocetane in order to find a binary surrogate mixture with similar performance characteristics to that of the HRD. A blend of approximately two-thirds n-hexadecane with one-third isocetane showed the most similar behavior based on conventional combustion metrics. Companion combustion modeling was then pursued using a combined detailed chemical kinetic mechanism for both n-hexadecane and isocetane. These modeling results show both the importance of isocetane in lengthening ignition delay, as well as the overall importance of chemical ignition delay as the dominating effect in the overall ignition delay of these binary blend fuels.

NUMERICAL SIMULATION FOR REDUCED CHEMICAL KINETIC MECHANISM: A CASE FOR CARBON MONOXIDE AND HYDROGEN

2018 ◽  
Author(s):  
Rafael Torres Teixeira ◽  
Rafaela Sehnem ◽  
Letícia Kaufmann ◽  
Daniela Buske ◽  
Regis Sperotto de Quadros
Keyword(s):  
Numerical Simulation ◽  
Carbon Monoxide ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Chemical Kinetic Mechanism
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