王建昕+清华+缸内直喷发动机氧化模型预测

ProceedingsCombustionInstitute

/locate/proci

ofthe

ProceedingsoftheCombustionInstitute33(2011)

3151–3158

Adetailedoxidationmechanismforthepredictionofformaldehydeemissionfrommethanol-gasoline

SIengines

FanZhang,ShijinShuai ,ZhiWang,XiaZhang,JianxinWang

StateKeyLaboratoryofAutomotiveSafetyandEnergy,TsinghuaUniversity,Beijing100084,China

Abstract

Iflow-contentmethanol-gasolineblendedfuelsareutilizedincurrentPFIgasolineengines,formalde-hydeemissionneedstobeintensivelyevaluated.Inthisstudy,adetailedcomprehensivemethanoloxida-tionmechanismwasdeveloped,basedonpresentreactionrateconstantandpathinformation.Thein uenceofCH,CH2(S),andCH2(T)radicalspeciesandnitricoxidewasconsideredinthemechanism.Shock-tubeand ow-reactordatawereusedtovalidatethemechanism.Numericalsimulationsofallsys-temswereconductedbyCHEMKIN-basedprograms.Inordertoconstructamethanol-gasolinemecha-nism,anoxidationmechanismofgasolinesurrogatewascombinedwiththemethanolmechanism.Thegasolinesurrogatemechanismwasformedwithiso-octane(iso-para nrepresentative),toluene(aromaticrepresentative),and1-hexene(ole nrepresentative).Themethanol-gasolinemechanismwasvalidatedbythejet-stirredreactor(JSR)experimentdata.Thesimulationresultsoftheproposedmechanismhaveagenerallygoodagreementwiththeexperimentaldata.Sequentially,theBoostenginecyclemodelwasestablishedandcoupledwiththemethanol-gasolinemechanismtosimulatetheformaldehydeemissionsofthelow-percentmethanol-gasolineblendedfuelsfromaSIengine,andalsoappliedtopredicttheemis-sionsofthehigh-percentblendedfuels.TheexperimentaldatafromtheSIenginewereobtainedbytheFTIR(Fouriertransforminfrared)spectrometer.ThesimulationresultsofSIenginesachieveagoodcon-sistencywiththeexperimentalresults.

Ó2010TheCombustionInstitute.PublishedbyElsevierInc.Allrightsreserved.

Keywords:Methanol;Gasoline;Oxidationmechanism;Emissions;Formaldehyde

1.Introduction

Asaliquidfuel,methanolcanbeproducedfromagreatnumberofdi erentrawandrenew-ablematerialresources.Theutilizationofcoal-generatedmethanolasapracticalalternativefuelisoneofthemostrealisticoptionsforChina,due

Correspondingauthor.Fax:+861062772515.

E-mail(S.

Shuai).

address:sjshuai@

tothe“oil-lean,gas-lacking,andcoal-rich”struc-tureofChineseenergyresources[1].However,formaldehydeemissionfrommethanolenginesisharmfultotheenvironmentaswellastohumanhealth.Thus,iflow-contentmethanol-gasolineblendedfuelsareutilizedincurrentPFI(PortFuelInjection)gasolineengines,formaldehydeemissionneedstobeintensivelyevaluated.

Thenumericalsimulationmethodcouldbedevelopedasausefulengineeringtooltoinvesti-gateunburnedmethanolandformaldehydeemissionsfrommethanolengines.Thus,detailed

1540-7489/$-seefrontmatterÓ2010TheCombustionInstitute.PublishedbyElsevierInc.Allrightsreserved.doi:10.1016/j.proci.2010.07.029