Numericalinvestigationofmulti-dimensionalcharacteristicsinsodiumcombustionOriginalResearchArticle

Multi-dimensionalsodiumcombustionbehaviorhasbeennumericallyinvestigatedinthepresentpaper.AnewcomputercodeAQUA-SFhasbeendevelopedforthispurpose.Thecodeincludestwosodiumcombustionmodels(socalled‘spraycombustion’and‘poolcombustion’),amassandheattransfermodelconsideringasix-fluxgasradiationandacoagulationandsedimentationmodelofsodiumoxideandhydroxideaerosols.Thesodiumspraycombustionrateisevaluatedbyasummationofthecombustionrateofeachsodiumdropletwithanindividualdiameter.Aflamesheetmodelisappliedtosituationswheresodiumspreadsoutonthefloorandapoolcombustiontakesplace.Themodelassumesaninfinitelythinflameabovethepoolsurfaceandisbasedonamassandenergybalanceintheflame.Astheresultsofnumericalanalysesofasodiumspraycombustiontest,alocationofhigh-temperaturecoreregionandamaximumtemperatureagreeswiththeexperiment.Goodagreementsofanoveralltransientbehaviorareobtainedinalarge-scalesodiumcombustiontestanalysis.Thenumericalanalysesalsodemonstratethatthedistributionsoftemperatureandchemicalspeciesconcentrationvarywithsodiumcombustionmodes.Ifsodiumscattersandthespraycombustionisdominant,thedistributionsvaryinspace.Whenalargeamountofsodiumexistsonafloorandthepoolareaisenlarged,thedistributionsaremoreuniforminspace.