简介：Thepaperconcernswiththedesignphilosophy,feasibilitystudy,aswellassomepeculiarfeaturesofIWHRwatertunnelforcavitationresearch.Thehighlightsworth-mentioningarethemaximumvelocityof35m/sandReynoldsnumberof1×10~7aswellastheprovisionofaspeciallydesignedairresorber.

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简介：Sincetrimandsinkagearesignificantwhilevesselsareadvancingforwardwithhighspeed,thepredictedvesselresistancebasedonrestrainedmodeltheoryorexperimentmaynotberealresistanceofvesselsduringvoyage.Itisnecessarytotaketheinfluenceofhullgestureintoaccountfororedictingtheresistanceofhigh-speedship.Inthepresentworktheresistanceproblemofhighspeedshipistreatedwiththeviscousflowtheory,andthedynamicmeshtechniqueisadoptedtocoincidewithvariationofhullgestureofhighspeedvesselonvoyage.ThesimulationofthemodelsofS60shipandatrimaranmovingintowingtankwithhighspeedareconductedbyusingtheabovetheoryandtechnique.Thecorrespondingnumericalresultsareingoodagreementwiththeexperimentaldata.Itindicatesthattheresistancepredictionforhighspeedvesselsshouldtakehullgestureintoconsiderationandthedynamicmeshmethodproposedhereiseffectiveincalculatingtheresistanceofhighspeedvessels.

简介：Inthispaper,astudyofthehigh-speedgasjetofarocketnozzleunderwaterwascarriedoutusingcommerciallyavailableCFDsoftwareFLUENTwithit'suser-defined-function.Thevolumeoffluidtechniquebasedonfinitevolumemethodwasadoptedtosolvethetime-dependentmultiphaseflowincludingacompressiblephase,andthePISOalgorithmwasincluded.Thecomputedresultsshowthatthisproblemwascalculatedsuccessfully.Thegasbubblebehindthenozzle,andthewavestructureexistinginhighlycompressedgasinwaterwerecapturedaccurately.

简介：Thisarticleinvestigatedanexistingsteadypatternofcollapseandrebound(disintegrationandaggregation)ofcavitationbubblesnearrigidboundaryinacousticfield.Adeformationprocessofcavitationbubblewasaccomplishedintwoacousticcycles,namely,asphericalbubblecollapsedtowardstheboundarytoitsminimumvolumeandthenreboundedandgrewintoatoroidalbubble(ortwoindividualbubbles)inoneacousticcycle,andthetoroidalbubble(ortwoindividualbubbles)collapsedtowardsthecenterofringtoitsminimumvolume,andthenreboundedintoasphericalbubbleinthenextacousticcycle.Inertiaforceplaysakeyroleinthetransitionbetweenthesetwostates.Themicrojetproducedduringthecollapseofsphericalbubbleandtheshockwaveproducedduringthecollapseoftoroidalbubble(ortwoindividualbubbles)impactstheboundaryalternately.Acavitationbubbleoperatinginthispatterncanthusbeaneffectivecorrosionmechanismofrigidboundary.

简介：Ahigh-orderfinitedifferencePadéschemealsocalledcompactschemeforsolvingKorteweg-deVries(KdV)equations,whichpreserveenergyandmassconservations,wasdevelopedinthispaper.Thisstructure-preservingalgorithmhasbeenwidelyappliedintheseyearsforitsadvantageofmaintainingtheinheritedproperties.Forspatialdiscretization,theauthorsobtainedanimplicitcompactschemebywhichspatialderivativetermsmaybeapproximatedthroughcombiningafewknots.Bysomenumericalexamplesincludingpropagationofsinglesolitonandinteractionoftwosolitons,theschemeisprovedtobeeffective.

简介：这篇文章主要在淹没，沉积交通和泛滥平原的词法变化上在开发综合2-D瞄准数字simulationmodel到期的tohigh沉积沉重的淹没流动。由于在泛滥平原的计算领域以内的内部、外部的边界和thearbitrary结构的复杂性，未组织的Finite-VolumeMethod(FVM)基于一个不规则的多角形网孔被得出以便complexboundaries的影响能集成于模拟。案例研究在更低的YellowRiver盆，在Huayuankou水文学车站的一个堤裂缝在被假定发生被进行1982的whena洪水规模在这个区域被承受。sedimentdeposition和侵蚀的模仿的空间分发能被用来相当解释“黄河的更低的部分的推迟的河”的自然现象。因为沉积免职anderosion被新值在结束修改，到variable-river-bed的水issimilar的淹没进程在模拟期间调节，这被结束每次走。团和动量conservationwere严格地在模拟期间列在后面。因此，由综合模拟模型的floodplainevolutions的预言，在这研究求婚了，如果一个泛滥平原的真实条件能详细被获得，能andaccurately足够地被给。

简介：Avariablecoefficient,rotation-modifiedextendedKortweg-deVries(vReKdV)modelisappliedtothestudyoftheSouthChinaSea(SCS),withfocusontheeffectsofthehigh-order(cubic)nonlinearityandtherotationonthedisintegrationprocessoflarge-amplitude(170m)InternalSolitaryWaves(ISWs)andthesemi-diurnalinternaltidepropagatingfromthedeepbasinstationtotheslopeandshelfregionsinacontinuouslystratifiedsystem.Thenumericalsolutionsshowthatthehigh-ordernonlinearitysigni-ficantlyaffectsthewaveprofilebyincreasingthewaveamplitudeandthephasespeedinthesimulatedarea.ItisshownthattheinitialKdV-typeISWwilldecayfasterwhentherotationdispersionisconsidered,howeverthewaveprofiledoesnotchangesignificantlyandtherotationeffectisnotimportant.Thesimulationsofthesemi-diurnalinternaltideindicatethatthephaseofthewaveprofileisshiftedearlierwhentherotationeffectisincluded.Asolitarywavepacketemergesontheshelf,andthewavespeedisalsogreaterwhenconsideringtherotationdispersion.Inaddition,theeffectsofthebackgroundcurrentsarediscussedfurtherinthispaper.ItisfoundthatthebackgroundcurrentsgenerallychangethemagnitudeandoccasionallychangethesignofthenonlinearcoefficientsinthenorthernSCS.

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简介：Thisarticleexperimentallyinvestigatedthepressureandcavitationcharacteristicsofhighvelocityflowoverasurfaceirregularitywithandwithoutaerationinanon-circulatingwatertunnelsystem.Thesurfaceirregularityisacylindricalprotrusionmadeofstainlesssteelof6mmdiameterand2mmheight.PressureswithandwithoutaerationweremeasuredwithMPX400Dpressuretransducersandreal-timelyacquiredbyaSINOCERAYE6263dataacquisitionsystem.Variationsinflowregimeswithandwithoutaerationwereobserved.Pressureprofilesandtheirvariationswithairconcentrationupperandlowercylindricalprotrusionontheinvertandobvertwallsweredetermined.Variationsofcavitationnumberwithairconcentrationlowercylindricalprotrusionwereanalyzed.Also,cavitationnumbersinthepresenceandabsenceofaerationwerecompared.

简介：Amethodispresentedtodeterminesignificantfrequenciesofoscillationsofcavitationstructuresfromhigh-speedcamerarecordingsofaflowarounda2-Dhydrofoil.ThetopviewofthesuctionsideofanNACA2412hydrofoilisstudiedinatransparenttestsectionofacavitationtunnelforselectedcloudcavitationregimeswithstrongoscillationsinducedbytheleading-edgecavityshedding.Theabilityofthemethodtoaccuratelydeterminethedominantoscillationfrequenciesisconfirmedbypressuremeasurements.Themethodcanresolvesubtleflowcharacteristicsthatarenotvisibletothenakedeye.Themethodcanbeusedfornoninvasiveexperimentalstudiesofoscillationsincavitatingflowswithadequatevisualaccesswhenpressuremeasurementsarenotavailableorwhensuchmeasurementswoulddisturbtheflow.