An advanced EMMS scheme for the prediction of drag coefficient under a 1.2 MWth CFBC isothermal flow-Part I: Numerical formulation

Nikolopoulos, A; Papafotiou, D; Nikolopoulos, N; Grammelis, P; Kakaras, E

dc.contributor.author	Nikolopoulos, A	en
dc.contributor.author	Papafotiou, D	en
dc.contributor.author	Nikolopoulos, N	en
dc.contributor.author	Grammelis, P	en
dc.contributor.author	Kakaras, E	en
dc.date.accessioned	2014-03-01T01:32:37Z
dc.date.available	2014-03-01T01:32:37Z
dc.date.issued	2010	en
dc.identifier.issn	0009-2509	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/20199
dc.subject	Clusters	en
dc.subject	EMMS	en
dc.subject	Fluidization	en
dc.subject	Hydrodynamics	en
dc.subject	Multiphase flow	en
dc.subject	Particle	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Algebraic modeling	en
dc.subject.other	CFD analysis	en
dc.subject.other	Circulating fluidized bed	en
dc.subject.other	Clusters	en
dc.subject.other	Co-existing	en
dc.subject.other	Conventional models	en
dc.subject.other	EMMS	en
dc.subject.other	Energy equation	en
dc.subject.other	Energy minimization	en
dc.subject.other	Gas solid two phase flow	en
dc.subject.other	Heterogeneous flow	en
dc.subject.other	Inert materials	en
dc.subject.other	Isothermal flows	en
dc.subject.other	Main characteristics	en
dc.subject.other	Momentum exchange	en
dc.subject.other	Multi-scale structures	en
dc.subject.other	Multiscales	en
dc.subject.other	Numerical formulation	en
dc.subject.other	Operating problems	en
dc.subject.other	Optimization software	en
dc.subject.other	Slip velocity	en
dc.subject.other	Agglomeration	en
dc.subject.other	Drag	en
dc.subject.other	Drag coefficient	en
dc.subject.other	Flow fields	en
dc.subject.other	Fluid dynamics	en
dc.subject.other	Fluidization	en
dc.subject.other	Fluidized bed process	en
dc.subject.other	Fluidized beds	en
dc.subject.other	Hydrodynamics	en
dc.subject.other	Industrial applications	en
dc.subject.other	Inert gases	en
dc.subject.other	Multiphase flow	en
dc.subject.other	Optimization	en
dc.subject.other	Computational fluid dynamics	en
dc.title	An advanced EMMS scheme for the prediction of drag coefficient under a 1.2 MWth CFBC isothermal flow-Part I: Numerical formulation	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.ces.2010.03.054	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.ces.2010.03.054	en
heal.language	English	en
heal.publicationDate	2010	en
heal.abstract	Range and size increment of industrial applications regarding Circulating Fluidized Bed (CFB) technology raise numerous design and operating problems. Further insight into the governing and complex multiphase flow physics regarding CFB operation can be provided by CFD analysis. However, it has been proven during the recent years that multi-scale phenomena occurring in CFB reactors cannot be accurately reproduced by conventional accurately reproduced by conventional models. Such model sare unable to accurately predict the moemntum exchange between the co-existing phases (gas and inert material) when calculating the drag coefficient. The main reason is that gas-solid two-phase flow features spatiotemporal multi-scale structures, named clusters, as the heterogensous flow field is developing. Aiming to evaluate the particles tendnecy to aggregate in clusters and describe the effects of this complicated mechanism on the main characteristisc of the induced multiphase flow field, the advanced Energy Minimization Multi-Scale (EMMS) analysis is applied. The EMMS scheme comprises of a set of equalities, constraints and a minimization energy equation, solved for a number of volume fraction's and slip velocitiy's values, using the optimization software General Algebraic Modeling System (GAMS). (C) 2010 Elsevier Ltd. All rights reserved.	en
heal.publisher	PERGAMON-ELSEVIER SCIENCE LTD	en
heal.journalName	Chemical Engineering Science	en
dc.identifier.doi	10.1016/j.ces.2010.03.054	en
dc.identifier.isi	ISI:000278603400017	en
dc.identifier.volume	65	en
dc.identifier.issue	13	en
dc.identifier.spage	4080	en
dc.identifier.epage	4088	en