An Informed Operator Based Genetic Algorithm for Tuning the Reaction Rate Parameters of Chemical Kinetics Mechanisms

Abstract This paper studies the crosslink and graft mechanism of hydrogenated-NBR/zinc di-methacrylate (HNBR/ZDMA) composites. The experiments to determine the rate constants of crosslink and graft reaction formulas are from Moving Die Rheometer (MDR) data. Comparison with experimental data and the solution of simultaneous ordinary differential equations for the crosslink and graft reactions are performed. Genetic algorithm optimization of the reaction rate constants allowed for simulation of crosslinking and graft reaction process. This simulation predicts that the HNBR/peroxide cure system will contain 0.1052-mole/l crosslink between matrix HNBR polymer at 2 phr.-peroxide concentration. The crosslink concentration of 0.1052-mole/l is composed of 0.0308-mole/l-addition reaction and 0.0744-mole/l-termination reaction. Moreover, the HNBR/ZDMA cure system contains 0.0148-mole/l graft of poly-ZDMA to HNBR and 0.0903-mole/l crosslink between matrix HNBR polymer at a 2 phr.-peroxide concentration.

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Application of Genetic Algorithm in Chemical Reaction Kinetics

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.79.71 ◽

2011 ◽

Vol 79 ◽

pp. 71-76 ◽

Cited By ~ 2

Author(s):

Wei Zhong ◽

Zhou Tian

Keyword(s):

Genetic Algorithm ◽

Reaction Kinetics ◽

Kinetic Parameters ◽

Chemical Kinetics ◽

Chemical Reaction ◽

Kinetic Equations ◽

Chemical Kinetic ◽

Chemical Reaction Kinetics ◽

Developing Trend

In this paper, a summary of Genetic Algorithm methods developed recent years applied in chemical reaction kinetics was presented. The applications of the Genetic Algorithm in reduction of the chemical reaction kinetics, estimation of the chemical kinetic parameters and calculation of the chemical kinetic equations were expounded here. Eventually, the confronted problem and developing trend of the application of Genetic Algorithm methods in chemical kinetics were reviewed.

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Technical note: Monte Carlo genetic algorithm (MCGA) for model analysis of multiphase chemical kinetics to determine transport and reaction rate coefficients using multiple experimental data sets

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-8021-2017 ◽

2017 ◽

Vol 17 (12) ◽

pp. 8021-8029 ◽

Cited By ~ 9

Author(s):

Thomas Berkemeier ◽

Markus Ammann ◽

Ulrich K. Krieger ◽

Thomas Peter ◽

Peter Spichtinger ◽

...

Keyword(s):

Experimental Data ◽

Genetic Algorithm ◽

Monte Carlo ◽

Kinetic Models ◽

Reaction Rate ◽

Rate Coefficients ◽

Model Parameters ◽

Data Sets ◽

Model Input ◽

Input Parameters

Abstract. We present a Monte Carlo genetic algorithm (MCGA) for efficient, automated, and unbiased global optimization of model input parameters by simultaneous fitting to multiple experimental data sets. The algorithm was developed to address the inverse modelling problems associated with fitting large sets of model input parameters encountered in state-of-the-art kinetic models for heterogeneous and multiphase atmospheric chemistry. The MCGA approach utilizes a sequence of optimization methods to find and characterize the solution of an optimization problem. It addresses an issue inherent to complex models whose extensive input parameter sets may not be uniquely determined from limited input data. Such ambiguity in the derived parameter values can be reliably detected using this new set of tools, allowing users to design experiments that should be particularly useful for constraining model parameters. We show that the MCGA has been used successfully to constrain parameters such as chemical reaction rate coefficients, diffusion coefficients, and Henry's law solubility coefficients in kinetic models of gas uptake and chemical transformation of aerosol particles as well as multiphase chemistry at the atmosphere–biosphere interface. While this study focuses on the processes outlined above, the MCGA approach should be portable to any numerical process model with similar computational expense and extent of the fitting parameter space.

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DYNAMICS OF COOPERATIVE REACTIONS BASED ON CHEMICAL KINETICS WITH REACTION SPEED: A COMPARATIVE ANALYSIS WITH SINGULAR AND NONSINGULAR KERNELS

Fractals ◽

10.1142/s0218348x22400485 ◽

2021 ◽

Author(s):

ZUBAIR AHMAD ◽

FARHAD ALI ◽

AISHA M. ALQAHTANI ◽

NAVEED KHAN ◽

ILYAS KHAN

Keyword(s):

Chemical Kinetics ◽

Reaction Rate ◽

Opposite Effect ◽

Classical Model ◽

Chemical Processes ◽

Systems Dynamics ◽

Fractional Operators ◽

Nonlinear Odes ◽

Fractional Models ◽

Reaction Speed

Chemical processes are constantly occurring in all existing creatures, and most of them contain proteins that are enzymes and perform as catalysts. To understand the dynamics of such phenomena, mathematical modeling is a powerful tool of study. This study is carried out for the dynamics of cooperative phenomenon based on chemical kinetics. Observations indicate that fractional models are more practical to describe complex systems’ dynamics, such as recording the memory in partial and full domains of particular operations. Therefore, this model is modeled in terms of classical-order-coupled nonlinear ODEs. Then the classical model is generalized with two different fractional operators of Caputo and Atangana–Baleanu in a Caputo sense. Some fundamental theoretical analysis for both the fractional models is also made. Reaction speeds for the extreme cases of positive/negative and no cooperation are also calculated. The graphical solutions are achieved via numerical schemes, and the simulations for both the models are carried out through the computational software MATLAB. It is observed that both the fractional models of Caputo and Atangana–Baleanu give identical results for integer order, i.e. [Formula: see text]. By decreasing the fractional parameters, the concentration profile of the substrate [Formula: see text] takes more time to vanish. Moreover, binding of first substrate increases the reaction rate at another binding site in the case of extreme positive cooperation, while the opposite effect is noticed for the case of negative cooperativity. Furthermore, the effects of other parameters on concentration profiles of different species are shown graphically and discussed physically.

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On Chemical Kinetics: Gas Phase Reaction Rate Theory . Harold S. Johnston. Ronald, New York, 1966. 372 pp., illus. $10.

Science ◽

10.1126/science.157.3788.535-b ◽

1967 ◽

Vol 157 (3788) ◽

pp. 535-536

Author(s):

Edward M. Eyring

Keyword(s):

New York ◽

Gas Phase ◽

Chemical Kinetics ◽

Reaction Rate ◽

Rate Theory ◽

Phase Reaction ◽

Gas Phase Reaction ◽

Reaction Rate Theory

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Thermodynamics and foundations of mass-action kinetics

Progress in Reaction Kinetics and Mechanism ◽

10.3184/007967405777874868 ◽

2005 ◽

Vol 30 (1-2) ◽

pp. 3-113 ◽

Cited By ~ 22

Author(s):

Miloslav Pekař

Keyword(s):

Chemical Kinetics ◽

Reaction Rate ◽

Chemical Potential ◽

Kinetic Equations ◽

Reaction Rates ◽

Equilibrium States ◽

Mass Action ◽

Rate Equations ◽

Mass Action Kinetics ◽

Non Equilibrium

A critical overview is given of phenomenological thermodynamic approaches to reaction rate equations of the type based on the law of mass-action. The review covers treatments based on classical equilibrium and irreversible (linear) thermodynamics, extended irreversible, rational and continuum thermodynamics. Special attention is devoted to affinity, the applications of activities in chemical kinetics and the importance of chemical potential. The review shows that chemical kinetics survives as the touchstone of these various thermody-namic theories. The traditional mass-action law is neither demonstrated nor proved and very often is only introduced post hoc into the framework of a particular thermodynamic theory, except for the case of rational thermodynamics. Most published “thermodynamic'’ kinetic equations are too complicated to find application in practical kinetics and have merely theoretical value. Solely rational thermodynamics can provide, in the specific case of a fluid reacting mixture, tractable rate equations which directly propose a possible reaction mechanism consistent with mass conservation and thermodynamics. It further shows that affinity alone cannot determine the reaction rate and should be supplemented by a quantity provisionally called constitutive affinity. Future research should focus on reaction rates in non-isotropic or non-homogeneous mixtures, the applicability of traditional (equilibrium) expressions relating chemical potential to activity in non-equilibrium states, and on using activities and activity coefficients determined under equilibrium in non-equilibrium states.

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A Novel Approach to Mechanism Reduction Optimization for an Aviation Fuel/Air Reaction Mechanism Using a Genetic Algorithm

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2131887 ◽

2004 ◽

Vol 128 (2) ◽

pp. 255-263 ◽

Cited By ~ 10

Author(s):

L. Elliott ◽

D. B. Ingham ◽

A. G. Kyne ◽

N. S. Mera ◽

M. Pourkashanian ◽

...

Keyword(s):

Genetic Algorithm ◽

Reaction Mechanism ◽

Reaction Rate ◽

Flame Structure ◽

Chemical Kinetic ◽

Reaction Scheme ◽

Operating Conditions ◽

Aviation Fuel ◽

Reduced Mechanism ◽

Genetic Algorithm Approach

This study presents a novel multiobjective genetic-algorithm approach to produce a new reduced chemical kinetic reaction mechanism to simulate aviation fuel combustion under various operating conditions. The mechanism is used to predict the flame structure of an aviation fuel/O2∕N2 flame in both spatially homogeneous and one-dimensional premixed combustion. Complex hydrocarbon fuels, such as aviation fuel, involve large numbers of reaction steps with many species. As all the reaction rate data are not well known, there is a high degree of uncertainty in the results obtained using these large detailed reaction mechanisms. In this study a genetic algorithm approach is employed for determining new reaction rate parameters for a reduced reaction mechanism for the combustion of aviation fuel-air mixtures. The genetic algorithm employed incorporates both perfectly stirred reactor and laminar premixed flame data in the inversion process, thus producing an efficient reaction mechanism. This study provides an optimized reduced aviation fuel-air reaction scheme whose performance in predicting experimental major species profiles and ignition delay times is not only an improvement on the starting reduced mechanism but also on the full mechanism.

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