• Title of article

    Structureofair–watertwo-phaseflowinhelicallycoiledtubesOriginalResearchArticle

  • Author/Authors

    YuichiMurai، نويسنده , , ShinjiYoshikawa، نويسنده , , Shin-ichiToda، نويسنده , , Masa-akiIshikawa، نويسنده , , FujioYamamoto، نويسنده ,

  • Issue Information
    روزنامه با شماره پیاپی سال 2006
  • Pages
    13
  • From page
    94
  • To page
    106
  • Abstract
    Air–watertwo-phaseflowinhelicallycoiledtubesisinvestigatedexperimentallytoelucidatetheeffectsofcentrifugalaccelerationontheflowregimemapandthespatialandthetemporalflowstructuredistribution.Threekindsoftesttubeswith20mminnerdiametersincludingastraighttubeareusedtocomparetheturbulentflowstructure.Superficialvelocitiesupto6m/saretestedsothatthecentrifugalFroudenumbercoversarangefrom0to3.Theinterfacialstructureisphotographedfromtwodirectionsbyahigh-speedvideosystemwithsynchronizedmeasurementoflocalpressurefluctuations.Theresultsrevealthattheflowtransitionlinealtersduetocentrifugalforceactingontheliquidphaseinthetube.Inparticular,thebubblyflowregimeisnarrowedsignificantly.Thepressurefluctuationamplitudegetslargerelativelytotheaveragepressurelossasvoidfractionincreases.Thefrequencyspectraofthepressurefluctuationhavepluralpeaksinthecaseofstrongcurvature,implyingthattheperiodicityofsluggingtwo-phaseflowiscollapsedbyaninternalsecondaryflowactivatedinsidetheliquidphase.Moreover,underlargeFroudenumberconditions,thesubstantialvelocityofthegasphasethatbiasestotheinnersideofthehelicalcoilisslowerthanthetotalsuperficialvelocitybecausetheliquidflowisallowedtopassthroughtheoutersideandsoresemblesaradialstratifiedflow.
  • Journal title
    Nuclear Engineering and Design Eslah
  • Serial Year
    2006
  • Journal title
    Nuclear Engineering and Design Eslah
  • Record number

    895976