摘要
Gas-solidtwo-phaseflowinacirculatingfluidizedbed(CFB)isaffectedbyoperatingconditions(e.g.,superficialgasvelocity,solidsinventory),materialpropertiesandgeometricfactors,suchastheentryandexitconfiguration.Inparticular,thesuspensionsection,whichislocatedbetweentheriserbottomandthesolidsrecycleinlet,affectsthehydrodynamicsintherisersignificantly.However,thesuspensionsectionhasreceivedlessattentioncomparedwithothergeometricfactors.Mostcomputationalfluiddynamics(CFD)simulations,especiallytwo-dimensionalsimulationsdonottakethisfactorintoaccount.Weperformedthree-dimensional,full-loopCFDsimulationswithadragcoefficientthatwasdeterminedbytheenergy-minimizationmulti-scalemodel,andinvestigatedtheflowbehavioroftwoCFBswithdifferentsuspension-sectionlengths.ThesimulationresuitsrevealedthattheaxialprofilesofvoidageintheriserwithalongersuspensionsectionaremorelikelyS-shaped,whereasthosewithshortersuspensionsectionsdecayexponentially.ThedependencesofsolidsfluxonsolidsinventorydifferinthetwoCFBs.Ashortersuspensionsectionmayresultinasmoothtransitionfromdilutetodensetransportwithoutintermediateaccumulativechoki-ng,whereasaIongersuspensionsectionmayleadtoachokingtransition.Thesesimulationresultsarequalitativelyconsistentwiththeflowbehaviorsdescribedinliterature.
出版日期
2019年02月12日(中国期刊网平台首次上网日期,不代表论文的发表时间)