Experimentalheattransferofsupercriticalcarbondioxideflowinginsidechannels(survey)OriginalResearchArticle

AnewreactorconceptunderdevelopmentatAECLhasthemaindesignobjectiveofachievinga50%reductioninunitenergycostrelativetoexistingreactordesigns.Theapproachbuildsonusingexistingoperatingsupercriticalwater(SCW)experienceandturbinesincoal-firedpowerplants. ThisSCWCANDU®researchincludesinvestigatingheattransferandpressuredropatsupercriticalconditionsusingcarbondioxideasamodellingfluidasacheaperandfasteralternativetousingSCW.Therefore,theobjectivesaretoassesstheworkthatwasdonewiththesupercriticalcarbondioxideandtounderstandthespecificsofheattransferattheseconditions. Ourexhaustiveliteraturesearch,whichincludedover450papers,showedthatthemajorityofexperimentaldatawereobtainedinverticaltubes,somedatainhorizontaltubesandjustfewinotherflowgeometries. Threemodesofheattransferatsupercriticalpressureshavebeenrecorded:(1)so-callednormalheattransfer,(2)improvedheattransfer,characterizedbyhigher-than-expectedheattransfercoefficient(HTC)valuesthaninthenormalheattransferregimeand(3)deterioratedheattransfer,characterizedbylower-than-expectedHTCvaluesthaninthenormalheattransferregime.