@PhDThesis{Azevedo:2013:DeSiCo,
author = "Azevedo, Claudia Gon{\c{c}}alves de",
title = "Desenvolvimento de um sistema compacto de combust{\~a}o sem chama
vis{\'{\i}}vel utilizando um injetor blurry para queima de
biocombust{\'{\i}}veis",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2013",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2013-10-14",
keywords = "combust{\~a}o sem chama vis{\'{\i}}vel, injetor blurry,
biocombust{\'{\i}}veis, flameless combustion, blurry injector,
biofuels.",
abstract = "As incertezas no fornecimento do petr{\'o}leo e as
preocupa{\c{c}}{\~o}es ambientais motivam o desenvolvimento de
novas tecnologias de combust{\~a}o empregando
biocombust{\'{\i}}veis, capazes de operar com elevada
efici{\^e}ncia t{\'e}rmica, baixo custo operacional e com
reduzido impacto ambiental. A combust{\~a}o sem chama
vis{\'{\i}}vel {\'e} uma tecnologia bastante promissora que
possibilita a redu{\c{c}}{\~a}o das emiss{\~o}es de poluentes
com uma alta efici{\^e}ncia de combust{\~a}o. O presente
trabalho tem como objetivo desenvolver um sistema compacto de
combust{\~a}o sem chama vis{\'{\i}}vel para a queima de
biocombust{\'{\i}}veis l{\'{\i}}quidos, utilizando-se um
injetor do tipo blurry. Esse tipo de injetor permite obter um
spray relativamente uniforme de gotas de tamanho reduzido, e forma
um {\^a}ngulo de cone estreito, favorecendo a
opera{\c{c}}{\~a}o do combustor sem chama vis{\'{\i}}vel.
Inicialmente, foram caracterizados injetores blurry com diferentes
geometrias de bocal usando-se {\'a}gua destilada, etanol
hidratado e biodiesel de soja B100. Foram determinados diversos
par{\^a}metros dos injetores, incluindo coeficientes de descarga,
di{\^a}metros representativos das gotas,
distribui{\c{c}}{\~o}es de di{\^a}metros de gotas e
{\^a}ngulos de cone do spray. Foram obtidas tamb{\'e}m
express{\~o}es para a predi{\c{c}}{\~a}o do tamanho m{\'e}dio
das gotas com os diferentes injetores testados. Em seguida foi
projetado, constru{\'{\i}}do e caracterizado um sistema compacto
de combust{\~a}o sem chama vis{\'{\i}}vel para a queima de
etanol hidratado, 96\% em volume. A caracteriza{\c{c}}{\~a}o
experimental do combustor foi realizada atrav{\'e}s da
determina{\c{c}}{\~a}o dos perfis de temperatura na c{\^a}mara
de combust{\~a}o, por meio de termopares e c{\^a}mera
termogr{\'a}fica, e da an{\'a}lise da composi{\c{c}}{\~a}o dos
gases de combust{\~a}o (UHC, \$CO_{2}\$, \$O_{2}\$,
\$NO_{x}\$ e CO), para diversos coeficientes de excesso de ar.
Verificou-se que o sistema de combust{\~a}o foi capaz de operar
no regime de combust{\~a}o sem chama vis{\'{\i}}vel para
coeficientes de ar entre 1,65 e 2,45, a uma pot{\^e}ncia
t{\'e}rmica de 2 kW, e para coeficientes de excesso de ar de 1,21
a 1,80, a uma pot{\^e}ncia t{\'e}rmica de 4 kW. A temperatura de
entrada do ar de combust{\~a}o ficou em torno de \$412^{º}\$C
para a pot{\^e}ncia de 2 kW e \$530^{º}\$C para a pot{\^e}ncia
de 4 kW. Os perfis de temperatura obtidos foram relativamente
homog{\^e}neos no interior da c{\^a}mara e as emiss{\~o}es
produzidas foram extremamente baixas para todas as
condi{\c{c}}{\~o}es de opera{\c{c}}{\~a}o estudadas. Para a
pot{\^e}ncia de 2 kW, foram obtidas temperaturas m{\'e}dias da
ordem de \$835^{º}\$C, com emiss{\~o}es de \$NO_{x}\$ entre
2,5 e 3 ppm e emiss{\~o}es de UHC entre 0,78 e 0,91 ppm. Para a
pot{\^e}ncia de 4 kW, foram obtidas temperaturas m{\'e}dias da
ordem de \$920^{º}\$C, com emiss{\~o}es de \$NO_{x}\$ entre
1,98 e 2,16 ppm e emiss{\~o}es de UHC entre 1,53 e 2,25 ppm.
ABSTRACT: The uncertainties in oil supply and environmental
concerns motivate the development of new combustion technologies
using biofuels, capable of operating with high thermal efficiency,
low operational cost and reduced environmental impact. Flameless
combustion is a promising technology that allows the reduction of
pollutant emissions with high combustion efficiency. The present
work aims to develop a compact system of flameless combustion for
burning liquid biofuel, using a blurry injector. The blurry
injector can generate a relatively uniform spray with small
droplets and forms a narrow cone angle, favoring the operation of
the flameless combustor. Initially, were characterized blurry
injectors with different nozzle geometries using distilled water,
hydrous ethanol and soybean biodiesel B100. Were determined
several parameters of the injectors, including discharge
coefficients, representative droplet diameters, distributions of
droplet diameters and spray cone angles. Also were obtained
expressions for the prediction of the average droplet diameters
with different injectors tested. Subsequently was projected, built
and characterized a compact flameless combustion system for
burning hydrous ethanol, 96\% by volume. The experimental
characterization of the combustor was performed by determination
of temperature profile in the combustion chamber, by thermocouples
and thermographic camera, and analyzing flue-gas composition (UHC,
\$CO_{2}\$, \$O_{2}\$, \$NO_{x}\$ and CO) for several air
excess coefficients. It was verified that the combustion system
was capable of operating in the flameless combustion regime for
excess air coefficients between 1.65 and 2.45 at a thermal power
of 2 kW, and for excess air coefficient of 1.21 to 1.80 at a
thermal power of 4 kW. The inlet air combustion temperature was
about \$412^{°}\$C for the power of 2 kW and \$530^{°}\$C for
the power of 4 kW. The temperature profiles obtained were
relatively homogeneous inside the chamber and the produced
emissions were extremely low for all studied operational
conditions. For the power of 2 kW, were obtained average
temperatures of the order of \$830^{°}\$C, with \$NO_{x}\$
emissions between 2.5 and 3 ppm and UHC emissions between 0.78 and
0.91 ppm. For the power of 4 kW, were obtained average
temperatures of the order of \$920^{°}\$C, with \$NO_{x}\$
emissions between 1.98 and 2.16 ppm and UHC emissions between1.53
and 2.25 ppm.",
committee = "Costa, Fernando de Souza (presidente/orientador) and Dourado,
Wladimyr Mattos da Costa and Mendon{\c{c}}a, Marcio Teixeira de
and Rodrigues, Lucilene de Oliveira and Lacava, Pedro Teixeira",
englishtitle = "Development of a compact flameless combustion system using a
blurry injector for burning biofuels",
language = "pt",
pages = "215",
ibi = "8JMKD3MGP7W/3F24DDL",
url = "http://urlib.net/ibi/8JMKD3MGP7W/3F24DDL",
targetfile = "publicacao.pdf",
urlaccessdate = "11 maio 2024"
}