简介:Thegrowthandcollapsebehaviorsofasinglecavitationbubblenearaheatedwallanditseffectontheheattransferarenumericallyinvestigated.Thepresentstudyisdesignedtorevealthemechanismofcavitationenhancedheattransferfromamicroscopicperspective.Inthesimulation,thetime-dependentNavier-Stokesequationsaresolvedinanaxisymmetrictwo-dimensionaldomain.Thevolumeoffluid(VOF)methodisemployedtotracktheliquid-gasinterface.Itisassumedthatthegasinsidethebubbleiscompressiblevapor,andthesurroundingliquidisincompressiblewater.Masstransferbetweentwophasesisignored.Thecalculatedbubbleprofileswerecomparedtotheavailableexperimentaldata,andagoodagreementwasobtained.Then,therelationshipamongbubblemotion,flowfieldandsurfaceheattransfercoefficientwasanalyzed.Onthisbasis,theeffectsofsuchfactorsastheinitialdistancebetweenthebubbleandthewall,theinitialvaporpressureandtheinitialbubblenucleussizeontheheattransferenhancementarediscussed.Thepresentstudyishelpfultounderstandtheheattransferphenomenoninpresenceofcavitationbubbleinliquid.