Fractional modeling for a chemical kinetic reaction in a batch reactor via nonlocal operator with power law kernel

2020 ◽  
Vol 542 ◽  
pp. 123494 ◽  
Author(s):  
Sania Qureshi ◽  
Shaheen Aziz
Keyword(s):  
Power Law ◽  
Batch Reactor ◽  
Chemical Kinetic ◽  
Nonlocal Operator ◽  
Kinetic Reaction ◽  
Fractional Modeling

Experimental and Modeling Study of the Combustion of Synthetic Jet Fuels: Naphtenic Cut and Blend With a GtL Jet Fuel

2016 ◽  
Author(s):  
Philippe Dagaut ◽  
Pascal Diévart
Keyword(s):  
Air Transportation ◽  
Chemical Kinetic ◽  
Jet Fuel ◽  
Synthetic Jet ◽  
Sensitivity Analyses ◽  
Jet Fuels ◽  
Kinetic Reaction ◽  
Experimental Database ◽  
Initial Fuel ◽  
Kinetics Of

Research on the production and combustion of synthetic jet fuels has recently gained importance because of their potential for addressing security of supply and sustainable air transportation challenges. The combustion of a 100% naphtenic cut that fits with typical chemical composition of products coming from biomass or coal liquefaction (C12.64H23.64; M=175.32 g.mol−1; H/C=1.87; DCN=39; density=863.1 g.L−1) and a 50% vol. mixture with Gas to Liquid from Shell (mixture: C11.54H23.35; M=161.83 g.mol−1; H/C=2.02; DCN=46; density=800.3 g.L−1) were studied in a jetstirred reactor under the same conditions (temperature, 550–1150 K; pressure, 10 bar; equivalence ratio, 0.5, 1, and 2; initial fuel concentration, 1000 ppm). Surrogate model-fuels were designed based on fuel composition and properties for simulating the kinetics of oxidation of these fuels. We used new model-fuels consisting of mixtures of n-decane, decalin, tetralin, 2-methylheptane, 3-methylheptane, n-propyl cyclohexane, and n-propylbenzene. The detailed chemical kinetic reaction mechanism proposed was validated using the entire experimental database obtained in the present work and for the oxidation of pure GtL, we used previous results. Kinetic computations involving reaction paths analyses and sensitivity analyses were used to interpret the results.

scholarly journals A comprehensive detailed chemical kinetic reaction mechanism for combustion of n-alkane hydrocarbons from n-octane to n-hexadecane

2009 ◽  
Vol 156 (1) ◽  
pp. 181-199 ◽  
Author(s):  
Charles K. Westbrook ◽  
William J. Pitz ◽  
Olivier Herbinet ◽  
Henry J. Curran ◽  
Emma J. Silke
Keyword(s):  
Reaction Mechanism ◽  
Chemical Kinetic ◽  
Kinetic Reaction ◽  
Detailed Chemical

A Computational Study of the Thermodynamic Conditions Leading to Autoignition in Nanosecond Pulsed Discharges

2019 ◽  
Author(s):  
Vyaas Gururajan ◽  
Riccardo Scarcelli ◽  
Anand Karpatne ◽  
Douglas Breden ◽  
Laxminarayan Raja ◽  
...  
Keyword(s):  
Chemical Structure ◽  
Computational Study ◽  
Batch Reactor ◽  
Chemical Kinetic ◽  
Electrode Erosion ◽  
Reactor Model ◽  
Modeling Tools ◽  
Thermodynamic Conditions ◽  
Streamer Propagation ◽  
Pulsed Discharges

Abstract Nanosecond pulsed discharges have attracted the attention of engine manufacturers due to the possibility of attaining distributed ignition sites that accelerate burn rates while resulting in very little electrode erosion. Multidimensional modeling tools currently capture the electrical structure of such discharges accurately, but resolving the chemical structure remains a challenging problem owing to the disparity of time-scales in streamer propagation (nanoseconds) and ignition phenomena (microseconds). The purpose of this study is to extend multidimensional results towards resolving the chemical structure in the wake of streamers (or the afterglow) by using a batch reactor model. This can afford the use of very detailed chemical kinetic information. The full non-equilibrium nature of the electrons is taken into account, along with fast gas heating, shock wave propagation, and thermal diffusion. The results shed light on ignition phenomena brought about by such discharges.

Modeling the Formation of Pollutant Emissions in Large-Bore, Lean-Burn Gas Engines

2017 ◽  
Author(s):  
Anamol Pundle ◽  
David G. Nicol ◽  
Philip C. Malte ◽  
Joel D. Hiltner
Keyword(s):  
Partial Oxidation ◽  
Flow Reactor ◽  
Batch Reactor ◽  
Plug Flow ◽  
Chemical Reactor ◽  
Chemical Kinetic ◽  
Pollutant Emissions ◽  
Lean Burn ◽  
Reciprocating Engines ◽  
Stroke Engine

This paper discusses chemical kinetic modeling used to analyze the formation of pollutant emissions in large-bore, lean-burn gas reciprocating engines. Pollutants considered are NOx, CO, HCHO, and UHC. A quasi-dimensional model, built as a chemical reactor network (CRN), is described. In this model, the flame front is treated as a perfectly stirred reactor (PSR) followed by a plug flow reactor (PFR), and reaction in the burnt gas is modeled assuming a batch reactor of constant-pressure and fixed-mass for each crank angle increment. The model treats full chemical kinetics. Engine heat loss is treated by incorporating the Woschni model into the CRN. The mass burn rate is selected so that the modeled cylinder pressure matches the experiment pressure trace. Originally, the model was developed for large, low speed, two-stoke, lean-burn engines. However, recently, the model has been formatted for the four-stroke, open-chamber, lean-burn engine. The focus of this paper is the application of the model to a four-stroke engine. This is a single-cylinder non-production variant of a heavy duty lean-burn engine of about 5 liters cylinder displacement Engine speed is 1500 RPM. Key findings of this work are the following. 1) Modeled NOx and CO are found to agree closely with emission measurements for this engine over a range of relative air-fuel ratios tested. 2) This modeling shows the importance of including N2O chemistry in the NOx calculation. For λ = 1.7, the model indicates that about 30% of the NOx emitted is formed by the N2O mechanism, with the balance from the Zeldovich mechanism. 3) The modeling shows that the CO and HCHO emissions arise from partial oxidation late in the expansion stroke as unburned charge remaining mixes into the burnt gas. 4) Model generated plots of HCHO versus CH4 emission for the four-stroke engine are in agreement with field data for large-bore, lean-burn, gas reciprocating engines. Also, recent engine tests show the correlation of UHC and CO emissions to crevice volume. These tests suggest that HCHO emissions also are affected by crevice flows through partial oxidation of UHC late in the expansion stroke.

scholarly journals A Single Pulse Shock Tube Study on the Pyrolysis of 2,5-Dimethylfuran

2015 ◽  
Vol 229 (4) ◽  
Author(s):  
Dominik F. Schuler ◽  
Clemens Naumann ◽  
Marina Braun-Unkhoff ◽  
Uwe Riedel ◽  
Friedhelm Zabel
Keyword(s):  
Gas Chromatography ◽  
Shock Tube ◽  
Reaction Mechanisms ◽  
Single Pulse ◽  
Product Distribution ◽  
Chemical Kinetic ◽  
Kinetic Reaction ◽  
Initial Concentration ◽  
Product Species ◽  
Tube Study

AbstractThe pyrolysis of 2,5-dimethylfuran has been studied in a single pulse shock tube equipped with fast probing device at temperatures between 1175 K and 1450 K and pressures of 8.0±0.5 bar. The initial concentration of 2,5-dimethylfuran diluted in argon (500 ppm) was much lower than in previous studies reported in the literature. Sixteen different product species were quantified by gas chromatography. The product distribution pattern was compared with the prediction of two comprehensive chemical kinetic reaction mechanisms taken from the literature. In general, the predictions of the mechanisms fit the results of the experiments; however, the comparison reveals some differences between the two mechanisms as well as between simulations and experiments.

scholarly journals Chemical kinetics and particle size effects of activated carbon for free chlorine removal from drinking water

2018 ◽  
Vol 14 (1) ◽  
pp. 19-26 ◽  
Author(s):  
Fanke Meng ◽  
Guoping Li ◽  
Binbin Zhang ◽  
Jinbin Guo
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Volume Flow Rate ◽  
Kinetic Constant ◽  
Chemical Kinetic ◽  
Free Chlorine ◽  
Order Kinetic ◽  
Potential Health ◽  
Kinetic Reaction ◽  
Chlorine Removal

Abstract Activated carbon is an economic material to grab free chlorine in drinking water to reduce potential health risks. In this research, chemical kinetic reaction of the activated carbon for free chlorine removal was studied, which exhibited the first order kinetic reaction performance. A relationship between the rate of chlorinated water flowing through the activated carbon, and the free chlorine (ClO−) concentrations before and after the reduction by activated carbon was obtained. The logarithm of the free chlorine concentration (lnC) was linearly related to the reciprocal of the volume flow rate (1/v). The slope was dependant on the kinetic constant of the activated carbon dechlorination reaction. This research is beneficial for the scientists and engineers to study the mechanism of the chemical kinetic reaction of the free chlorine removal by activated carbon and design activated carbon-loaded water purification reactors.

scholarly journals Fuel-Rich Premixed n-Heptane/Toluene Flame: a Molecular Beam Mass Spectrometry and Chemical Kinetic Study

2014 ◽  
Vol 16 (2-3) ◽  
pp. 219
Author(s):  
D.A. Knyazkov ◽  
N.A. Slavinskaya ◽  
A.M. Dmitriev ◽  
A.G. Shmakov ◽  
O.P. Korobeinichev ◽  
...  
Keyword(s):  
Mole Fraction ◽  
Volume Ratio ◽  
Chemical Kinetic ◽  
Liquid Volume ◽  
Data Set ◽  
Kinetic Reaction ◽  
Molecular Beam Mass Spectrometry ◽  
Soot Precursors ◽  
Kinetic Mechanisms ◽  
Fuel Surrogates

<p>The mole fraction profiles of major flame species and intermediates including PAH precursors are measured in an atmospheric premixed burner-stabilized fuel-rich (<em>φ</em> = 1.75) <em>n</em>-heptane/toluene/O<sub>2</sub>/Ar flame (<em>n</em>-heptane/toluene ratio is 7:3 by liquid volume). These data are simulated with a detailed, extensively validated chemical kinetic reaction mechanism for combustion of <em>n</em>-heptane/toluene mixture, involving the reactions of PAH formation. The mechanism is extended with cross reactions for <em>n</em>-heptane and toluene derivatives. A satisfactory agreement between the new experimental data on the structure of <em>n</em>-heptane/toluene flame and the numerical simulations is observed. The mechanism reported can be successfully used in the models of practical fuel surrogates for reproducing the formation of soot precursors. The analysis of the reaction pathways shows that in the flame of the <em>n</em>-heptane/toluene blend (7:3 liquid volume ratio) the reactions dominant for the formation of the first aromatic ring (benzene and phenyl) are as those typical for pure toluene flames. The discrepancies between the measured and calculated species mole fractions are detected as well. The steps for the mechanism improvements are determined on the basis of the sensitivity analysis performed. To our knowledge, the measurements of mole fraction profiles of PAH and intermediates reported here, are the first of its kind and represent an unique data set extremely important for validation of chemical kinetic mechanisms for combustion of practical fuels.</p><p> </p>

Inference of Chemical Reaction Networks Using Hybrid S-system Models

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
Dominic P Searson ◽  
Mark J Willis ◽  
Simon J Horne ◽  
Allen R Wright
Keyword(s):  
Chemical Reaction ◽  
Power Law ◽  
Network Inference ◽  
Batch Reactor ◽  
Reaction Network ◽  
Chemical Reaction Networks ◽  
Chemical Reaction Network ◽  
Reaction Networks ◽  
Fed Batch ◽  
System Equations

This article demonstrates, using simulations, the potential of the S-system formalism for the inference of unknown chemical reaction networks from simple experimental data, such as that typically obtained from laboratory scale reaction vessels. Virtually no prior knowledge of the products and reactants is assumed. S-systems are a power law formalism for the canonical approximate representation of dynamic non-linear systems. This formalism has the useful property that the structure of a network is dictated only by the values of the power law parameters. This means that network inference problems (e.g. inference of the topology of a chemical reaction network) can be recast as parameter estimation problems. The use of S-systems for network inference from data has been reported in a number of biological fields, including metabolic pathway analysis and the inference of gene regulatory networks. Here, the methodology is adapted for use as a hybrid modelling tool to facilitate the reverse engineering of chemical reaction networks using time series concentration data from fed-batch reactor experiments. The principle of the approach is demonstrated with noisy simulated data from fed-batch reactor experiments using a hypothetical reaction network comprising 5 chemical species involved in 4 parallel reactions. A co-evolutionary algorithm is employed to evolve the structure and the parameter values of the S-system equations concurrently. The S-system equations are then interpreted in order to construct a network diagram that accurately reflects the underlying chemical reaction network.

Chemical Kinetic Mechanism Reduction Scheme for Diesel Fuel Surrogate

2014 ◽  
Vol 541-542 ◽  
pp. 1006-1010 ◽  
Author(s):  
Hiew Mun Poon ◽  
Hoon Kiat Ng ◽  
Su Yin Gan ◽  
Kar Mun Pang ◽  
Jesper Schramm
Keyword(s):  
Diesel Fuel ◽  
Batch Reactor ◽  
Cetane Number ◽  
Kinetic Mechanism ◽  
Chemical Kinetic ◽  
Species Number ◽  
Reduction Scheme ◽  
Mechanism Reduction ◽  
Chemical Kinetic Mechanism ◽  
Fuel Surrogate

In this study, performance of the DRG-based chemical kinetic mechanism reduction techniques was evaluated using a diesel fuel surrogate model, which is the n-hexadecane mechanism. Following that, a new mechanism reduction scheme was developed to generate a reduced mechanism which is suitable to be applied in diesel engine applications.As a result, areduced mechanism with 49 species and 97 elementary reactions was successfully derived from the detailed mechanismwithan overall 97% reduction in species number and computational runtime in zero-dimensional closed homogeneous batch reactor simulations. After that, the reduced n-hexadecane mechanism was applied to simulate spray combustion in a constant volume bomb using OpenFOAM software. Results show that n-hexadecane alone is inappropriate to be employed as a single-component diesel surrogate as its high cetane number has resulted in advanced ignition timing. This agrees with recent study andthus fuel blending is suggested in order to match the diesel fuel kinetics and compositions.

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