Artigo
Numerical analysis of flameless combustion in a compact chamber burning hydrous ethanol
Registro en:
SIQUEIRA, B. O. P. e S. et al. Numerical analysis of flameless combustion in a compact chamber burning hydrous ethanol. Journal of Multidisciplinary Engineering Science and Technology (JMEST), [S. I.], v. 8, n. 4, p. 13781-13796, Apr. 2021.
Autor
Siqueira, Bruna Oliveira Passos e Silva
Nascimento, Marco A. R.
Rodrigues, Lucilene de Oliveira
Azevedo, Cláudia Gonçalves de
Rodriguez, Christian Jeremi Coronado
Souza, Tulio Augusto Zucareli de
Institución
Resumen
This paper presents the numerical
simulation of a compact laboratory-scale
combustion chamber designed to operate with
flameless combustion technology, using hydrous
ethanol as fuel. The purpose of the study is to
validate the combustion modeling to perform a
more in-depth analysis of the combustion
atmosphere based on the temperature profiles,
velocity fields and emissions of UHC, CO and NO
to verify the development of the flameless
combustion regime from burning liquid biofuels.
In this paper, two different combustions models
had their results of the numerical simulations
analyzed: the Eddy Dissipation Concept (EDC)
and the hybrid model Finite Rate / Eddy
Dissipation (FRED). The temperature profiles and
UHC, CO and NO concentrations obtained in the
numerical simulations showed good agreement
with the experimental results for the combustion
modeling by the FRED model, with maximum
deviations between 1.0 and 12.5% between the
numerical and experimental temperature profiles
and maximum deviations of 6% for the UHC, CO
and NO numerical and experimental emission
rates, allowing the validation of the developed
numerical procedure. The EDC model hasn’t
satisfactorily reproduced the turbulent and
chemical interactions of the combustion reactions
that occur in the flameless of hydrous ethanol,
significantly affecting the temperature distribution
in the combustion atmosphere which presented
maximum deviations of the order of 25% in
relation to the experimental results. The validation
of the combustion modeling by the FRED model
allowed a global analysis of the combustion
atmosphere and the numerical results revealed
that during the experiment the combustion
chamber used in the present study didn’t operate
in the flameless regime, but in the transition
regime between conventional combustion and the
flameless combustion regime. The numerical
analysis showed that a longer operation time of
the experimental combustion system is necessary
for the development of the flameless.