Title of article :
Fluctuationcharacteristicsofheatingsurfacetemperaturenearanobstacleintransientboilingtwo-phaseflowinaverticalannularchannelOriginalResearchArticle
Author/Authors :
TFukano، نويسنده , , SMori، نويسنده , , TNakagawa، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2003
Abstract :
Whenaflowobstructionsuchasaspacerissetinaboilingtwo-phaseflowwithinanannularchannel,theinnertubeofwhichisusedasaheater,thetemperatureonthesurfaceoftheheatertubeisseverelyaffectedbytheexistenceofthespacer.Insomecasesthespacerhasacoolingeffect,andinothercasesitcausesthedryoutofthecoolingwaterfilmontheheatingsurfaceresultingintheburnoutofthetube.Inthepresentpaperwewilldiscusstemperaturefluctuationsinrelationtothechangeintheflowconfigurationnearthecylindricalspacerintransientboilingtwo-phaseflowcausedbythestepwisechangeoftheoperationparameterssuchastheheatflux,themassflowrate,andtheinletqualityofthetestsection.Asaresultitisconcludedthat:Eveniftheflowpatternchangesrapidlybyastepwisechangeofanoperationparameter,thetransitionofflowproceedssafelyprovidedthatthechangecausestheincreaseofvaporvelocity,i.e.theincreaseoftheshearforcewhichisactingonliquidfilmflow.Ontheotherhandifthechangecausesthedecreaseofthevaporvelocity,itmustbenoticedthatthetransientburnoutpossiblyoccursevenwhentheoperatingconditionafterthechangeislessthanthesteadyburnoutcondition.
Journal title :
Nuclear Engineering and Design Eslah
Journal title :
Nuclear Engineering and Design Eslah
