0
Research Papers: Fuel Combustion

Development of the Rate-Controlled Constrained-Equilibrium Method for Modeling of Ethanol Combustion

[+] Author and Article Information
Ghassan Nicolas, Hameed Metghalchi

Mechanical and Industrial
Engineering Department,
Northeastern University,
Boston, MA 02115

Contributed by the Advanced Energy Systems Division of ASME for publication in the JOURNAL OF ENERGY RESOURCES TECHNOLOGY. Manuscript received July 27, 2015; final manuscript received August 12, 2015; published online November 17, 2015. Assoc. Editor: Reza H. Sheikhi.

J. Energy Resour. Technol 138(2), 022205 (Nov 17, 2015) (11 pages) Paper No: JERT-15-1286; doi: 10.1115/1.4031511 History: Received July 27, 2015; Revised August 12, 2015

The rate-controlled constrained-equilibrium method (RCCE) has been further developed to model the combustion process of ethanol air mixtures. The RCCE is a reduction technique based on local maximization of entropy or minimization of a relevant free energy at any time during the nonequilibrium evolution of the system subject to a set of kinetic constraints. An important part of RCCE calculation is determination of a set of constraints that can guide the nonequilibrium mixture to the final stable equilibrium state. In this study, 16 constraints have been developed to model the nonequilibrium ethanol combustion process. The method requires solution of 16 differential equations for the corresponding constraint potentials. Ignition delay calculations of ethanol oxidizer mixtures using RCCE have been compared to those of detailed chemical kinetics using 37 species and 235 reactions. Agreement between the two models is very good. In addition, ignition delay of C2H5OH/O2/Ar mixtures using RCCE has been compared with the experimental measurements in the shock tube and excellent agreement has been reached validating the RCCE calculation.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Fig. 1

Hierarchical structure of the present ethanol oxidation mechanism [24]

Grahic Jump Location
Fig. 2

RCCE reaction flow diagram for C2H5OH/O2/diluent mixtures. The boxes show the constraints.

Grahic Jump Location
Fig. 3

Variation of elemental constraint potentials versus time under constant (E, V) conditions

Grahic Jump Location
Fig. 4

Variation of nonelemental constraint potentials versus time under constant (E, V) conditions

Grahic Jump Location
Fig. 5

Variation of nonelemental constraint potentials versus time under constant (E, V) conditions

Grahic Jump Location
Fig. 6

Comparison in temperature profile between RCCE (dashed lines) and DKM (solid lines) for different initial pressures (1–10 atm) under constant (E, V) conditions

Grahic Jump Location
Fig. 7

Comparison in temperature profile between RCCE (dashed lines) and DKM (solid lines) for different initial temperatures (900–1300 K) under constant (E, V) conditions

Grahic Jump Location
Fig. 8

Comparison in temperature profile between RCCE (dashed lines) and DKM (solid lines) for different equivalence ratios (0.8–1.2) under constant (E, V) conditions

Grahic Jump Location
Fig. 9

Comparison in log |T − Ti| temperature profiles between RCCE (dashed lines) and DKM (solid lines) for lean mixtures under constant (E, V) conditions

Grahic Jump Location
Fig. 10

Comparison in major species concentrations (C2H5OH, O2, H2O, and CO2) for a lean mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 11

Comparison in major species concentrations (CH3CH2O, CH3CHOH, CH2CH2OH, CH3CHO, and HO2) for a lean mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 12

Comparison in major species concentrations (C2H4, H2O2, H2O, and CH2O) for a lean mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 13

Comparison in log |T − Ti| temperature profiles between RCCE (dashed lines) and DKM (solid lines) for rich mixtures under constant (E, V) conditions

Grahic Jump Location
Fig. 14

Comparison in major species concentrations (C2H5OH, O2, H2O, and CO2) for a rich mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 15

Comparison in major species concentrations (CH3CH2O, CH3CHOH, CH2CH2OH, CH3CHO, and HO2) for a rich mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 16

Comparison in major species concentrations (C2H4, H2O2, H2O, and CH2O) for a rich mixture between RCCE (dashed lines) and DKM (solid lines) under constant (E, V) conditions

Grahic Jump Location
Fig. 17

Comparison in ignition delay time between RCCE and shock tube experiments [17] for C2H5OH/O2/Ar mixture (90% dilution) at Phi = 1.0 and P = 1 atm and temperature varying from 1298 to 1660 K under constant (E, V) conditions

Grahic Jump Location
Fig. 18

Comparison in ignition delay time between RCCE and shock tube experiments [17] for C2H5OH/O2/Ar mixture (90% dilution) at Phi = 1.0 and P = 2 atm and temperature varying from 1295 to 1614 K under constant (E, V) conditions

Grahic Jump Location
Fig. 19

Comparison in ignition delay time between RCCE and shock tube experiments [17] for C2H5OH/O2/Ar mixture (90% dilution) at Phi = 2.0 and P = 1 atm and temperature varying from 1303 to 1660 K under constant (E, V) conditions

Grahic Jump Location
Fig. 20

Comparison in ignition delay time between RCCE and shock tube experiments [17] for C2H5OH/O2/Ar mixture (90% dilution) at Phi = 2.0 and P = 2 atm and temperature varying from 1288 to 1597 K under constant (E, V) conditions

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In