The prediction of pulverized greek lignite combustion in axisymmetric furnaces

Anagnostopoulos, JS; Sargianos, NP; Bergeles, G

dc.contributor.author	Anagnostopoulos, JS	en
dc.contributor.author	Sargianos, NP	en
dc.contributor.author	Bergeles, G	en
dc.date.accessioned	2014-03-01T01:09:35Z
dc.date.available	2014-03-01T01:09:35Z
dc.date.issued	1993	en
dc.identifier.issn	0010-2180	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/11093
dc.subject.classification	Thermodynamics	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Engineering, Multidisciplinary	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Coal combustion	en
dc.subject.other	Coal fueled furnaces	en
dc.subject.other	Combustion	en
dc.subject.other	Flame research	en
dc.subject.other	Mathematical models	en
dc.subject.other	Oxidation	en
dc.subject.other	Pulverized fuel	en
dc.subject.other	Axisymmetric furnaces	en
dc.subject.other	Char oxidation reaction	en
dc.subject.other	Devolatilization	en
dc.subject.other	Flame stability model	en
dc.subject.other	Lignite	en
dc.subject.other	coal	en
dc.subject.other	lignite	en
dc.subject.other	article	en
dc.subject.other	combustion	en
dc.subject.other	controlled study	en
dc.subject.other	furnace	en
dc.subject.other	gas	en
dc.subject.other	greece	en
dc.subject.other	mathematical computing	en
dc.subject.other	mathematical model	en
dc.subject.other	phase transition	en
dc.subject.other	stochastic model	en
dc.subject.other	technique	en
dc.subject.other	volatilization	en
dc.title	The prediction of pulverized greek lignite combustion in axisymmetric furnaces	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/0010-2180(93)90033-Y	en
heal.identifier.secondary	http://dx.doi.org/10.1016/0010-2180(93)90033-Y	en
heal.language	English	en
heal.publicationDate	1993	en
heal.abstract	A general numerical method for calculating pulverized coal combustion in axisymmetric geometries is utilized, aiming at the optimization of combustion model constants for Greek lignite. The two-equation, 'κ-ε' turbulence model is used for the gas phase, whereas a stochastic approach, based on the lagrangian technique, is used for the particulate phase. The method employs a 'constant devolatilization rate' model for both the volatiles and the moisture of the fuel, a char combustion model, a relation of the 'eddy-dissipation' family for the reaction rate of the gaseous mixture, and the 'nonequilibrium diffusion' radiation model. The maximum permissible rate of devolatilization and the preexponential factor of the char oxidation reaction rate are optimized in order to match available experimental data for Greek lignite; these parameters were found to influence considerably, albeit in a different fashion, the combustion process in cylindrical furnaces operating on pulverized lignite. Finally, the liftoff characteristics of the lignite flame were also predicted using a temperature criterion, as well as a flame stability model.A general numerical method for calculating pulverized coal combustion in axisymmetric geometries is utilized, aiming at the optimization of combustion model constants for Greek lignite. The two-equation, 'k-ε' turbulence model is used for the gas phase, whereas a stochastic approach, based on the lagrangian technique, is used for the particulate phase. The method employs a 'constant devolatilization rate' model for both the volatiles and the moisture of the fuel, a char combustion model, a relation of the 'eddy-dissipation' family for the reaction rate of the gaseous mixture, and the 'nonequilibrium diffusion' radiation model. The maximum permissible rate of devolatilization and the preexponential factor of the char oxidation reaction rate are compared in order to match available experimental data for Greek lignite; these parameters were found to influence considerably albeit in a different fashion, the combustion process in cylindrical furnaces operating on pulverized lignite. Finally, the liftoff characteristics of the lignite flame were also predicted using a temperature criterion, as well as a flame stability model.	en
heal.publisher	ELSEVIER SCIENCE INC	en
heal.journalName	Combustion and Flame	en
dc.identifier.doi	10.1016/0010-2180(93)90033-Y	en
dc.identifier.isi	ISI:A1993KK99400002	en
dc.identifier.volume	92	en
dc.identifier.issue	3	en
dc.identifier.spage	209	en
dc.identifier.epage	221	en