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New integration techniques for chemical kinetic rate equations. I - Efficiency comparisonA comparison of the efficiency of several recently developed numerical techniques for solving chemical kinetic rate equations is presented. The solution procedures examined include two general-purpose codes, EPISODE and LSODE, developed as multipurpose differential equation solvers, and three specialzed codes, CHEMEQ, CREK1D, and GCKP84, developed specifically for chemical kinetics. The efficiency comparison is made by applying these codes to two practical combustion kinetics problems. Both problems describe adiabatic, constant-pressure, gas-phase chemical reactions and include all three combustion regimes: induction, heat release, and equilibration. The comparison shows that LSODE is the fastest routine currently available for solving chemical kinetic rate equations. An important finding is that an iterative solution of the algebraic enthalpy conservation equation for temperature can be significantly faster than evaluation of the temperature by integration of its time derivative. Significant increases in computational speed are realized by updating the reaction rate constants only when the temperature change exceeds an amount Delta-T that is problem dependent. An approximate expression for the automatic evaluation of Delta-T is presented and is shown to result in increased computational speed.
Document ID
19860053352
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
Authors
Radhakrishnan, K.
(NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 12, 2013
Publication Date
January 1, 1986
Publication Information
Publication: Combustion Science and Technology
Volume: 46
Issue: 1-2
ISSN: 0010-2202
Subject Category
Inorganic And Physical Chemistry
Accession Number
86A38090
Funding Number(s)
CONTRACT_GRANT: NAG3-294
Distribution Limits
Public
Copyright
Other

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