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Title: A tabulated chemistry approach for numerical modeling of diesel spray evaporation in a 'stabilized cool flame' environment

Abstract

Droplet evaporation in a 'stabilized cool flame' environment leads to a homogeneous, heated air-fuel vapor mixture that can be subsequently either burnt or utilized in fuel-reforming applications for fuel cell systems. The paper investigates the locally occurring physico-chemical phenomena in an atmospheric pressure, diesel spray, stabilized cool flame reactor, utilizing a tabulated chemistry approach in conjunction with a two-phase, Eulerian-Lagrangian computational fluid dynamics code. Actual diesel oil physical properties are used to model spray evaporation in the two-phase simulations, whereas the corresponding chemistry is represented by n-heptane. A lookup table is constructed by performing a plethora of perfectly stirred reactor simulations, utilizing a semidetailed n-heptane oxidation chemical kinetics mechanism. The overall exothermicity of the preignition n-heptane oxidation chemistry and the fuel consumption rates are examined as a function of selected independent parameters, namely temperature, fuel concentration, and residence time; their influence on cool flame reactivity is thoroughly studied. It is shown that the tabulated chemistry approach allows accurate investigation of the chemical phenomena with low computational cost. The two-phase flow inside the stabilized cool flame reactor is simulated, utilizing the developed lookup table. Predictions are presented for a variety of test cases and are compared to available experimental data, withmore » satisfactory agreement. Model validation tests indicate that prediction quality improves with increasing values of air temperature at the reactor's inlet. (author)« less

Authors:
;  [1]
  1. Heterogeneous Mixtures and Combustion Systems, Thermal Engineering Section, School of Mechanical Engineering, National Technical University of Athens, Heroon Polytechniou 9, Polytechnioupoli Zografou, 15780 Athens (Greece)
Publication Date:
OSTI Identifier:
20727304
Resource Type:
Journal Article
Resource Relation:
Journal Name: Combustion and Flame; Journal Volume: 145; Journal Issue: 1-2; Other Information: Elsevier Ltd. All rights reserved
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 42 ENGINEERING; 33 ADVANCED PROPULSION SYSTEMS; 30 DIRECT ENERGY CONVERSION; DIESEL FUELS; EVAPORATION; SPRAYS; DROPLETS; VAPORS; MATHEMATICAL MODELS; COMBUSTION KINETICS; FURNACES; BOILERS; INTERNAL COMBUSTION ENGINES; GAS TURBINES; HYDROCARBON FUEL CELLS

Citation Formats

Kolaitis, D.I., and Founti, M.A. A tabulated chemistry approach for numerical modeling of diesel spray evaporation in a 'stabilized cool flame' environment. United States: N. p., 2006. Web. doi:10.1016/j.combustflame.2005.10.008.
Kolaitis, D.I., & Founti, M.A. A tabulated chemistry approach for numerical modeling of diesel spray evaporation in a 'stabilized cool flame' environment. United States. doi:10.1016/j.combustflame.2005.10.008.
Kolaitis, D.I., and Founti, M.A. Sat . "A tabulated chemistry approach for numerical modeling of diesel spray evaporation in a 'stabilized cool flame' environment". United States. doi:10.1016/j.combustflame.2005.10.008.
@article{osti_20727304,
title = {A tabulated chemistry approach for numerical modeling of diesel spray evaporation in a 'stabilized cool flame' environment},
author = {Kolaitis, D.I. and Founti, M.A.},
abstractNote = {Droplet evaporation in a 'stabilized cool flame' environment leads to a homogeneous, heated air-fuel vapor mixture that can be subsequently either burnt or utilized in fuel-reforming applications for fuel cell systems. The paper investigates the locally occurring physico-chemical phenomena in an atmospheric pressure, diesel spray, stabilized cool flame reactor, utilizing a tabulated chemistry approach in conjunction with a two-phase, Eulerian-Lagrangian computational fluid dynamics code. Actual diesel oil physical properties are used to model spray evaporation in the two-phase simulations, whereas the corresponding chemistry is represented by n-heptane. A lookup table is constructed by performing a plethora of perfectly stirred reactor simulations, utilizing a semidetailed n-heptane oxidation chemical kinetics mechanism. The overall exothermicity of the preignition n-heptane oxidation chemistry and the fuel consumption rates are examined as a function of selected independent parameters, namely temperature, fuel concentration, and residence time; their influence on cool flame reactivity is thoroughly studied. It is shown that the tabulated chemistry approach allows accurate investigation of the chemical phenomena with low computational cost. The two-phase flow inside the stabilized cool flame reactor is simulated, utilizing the developed lookup table. Predictions are presented for a variety of test cases and are compared to available experimental data, with satisfactory agreement. Model validation tests indicate that prediction quality improves with increasing values of air temperature at the reactor's inlet. (author)},
doi = {10.1016/j.combustflame.2005.10.008},
journal = {Combustion and Flame},
number = 1-2,
volume = 145,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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