Simulation of Heat Transfer with the Growth and Collapse of a Cavitation Bub- ble Near the Heated Wall

(整期优先)网络出版时间:2013-04-14
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Thegrowthandcollapsebehaviorsofasinglecavitationbubblenearaheatedwallanditseffectontheheattransferarenumericallyinvestigated.Thepresentstudyisdesignedtorevealthemechanismofcavitationenhancedheattransferfromamicroscopicperspective.Inthesimulation,thetime-dependentNavier-Stokesequationsaresolvedinanaxisymmetrictwo-dimensionaldomain.Thevolumeoffluid(VOF)methodisemployedtotracktheliquid-gasinterface.Itisassumedthatthegasinsidethebubbleiscompressiblevapor,andthesurroundingliquidisincompressiblewater.Masstransferbetweentwophasesisignored.Thecalculatedbubbleprofileswerecomparedtotheavailableexperimentaldata,andagoodagreementwasobtained.Then,therelationshipamongbubblemotion,flowfieldandsurfaceheattransfercoefficientwasanalyzed.Onthisbasis,theeffectsofsuchfactorsastheinitialdistancebetweenthebubbleandthewall,theinitialvaporpressureandtheinitialbubblenucleussizeontheheattransferenhancementarediscussed.Thepresentstudyishelpfultounderstandtheheattransferphenomenoninpresenceofcavitationbubbleinliquid.