Toclarifytheinfluencesofthetipclearanceflowsontheunsteadycavitatingflow,thethree-dimensionalunsteadycavitatingflowsthroughboththetwo-dimensionalcascadesandthethree-dimensionalinducerwithandwithouttipclearanceareperformednumerically.ThegoverningequationsforthecompressiblefluidflowwiththeDESturbulencemodelareemployedwiththeassumptionoftheisentropicprocessofliquidphase.Theevolutionofcavitiesisrepresentedasthesource/sinkofvaporphase.Thebasicequationsinthecurvelinearcoordinatearesolvedbythefinitedifferencemethod.Astheresultsofthethree-dimensionalcavitatingflowsthroughthetwo-dimensionalcascades,thetipclearanceflowsfromthepressuresidetothesuctionsideofthebladeproducesthetipvortexcavitation,whichaffectsthesheetcavitationontheleadingedgeofthenextbladeandenhancestheblockageeffectnearthecasingthantheflowswithouttipclearance.Ontheotherhand,inthecaseofthethree-dimensionalinducer,thelargebackflowcavitationisobservedaroundtheinletoftheinducer,wherethecavitiesaredevelopedonthecasingbythetipclearanceflows.Thelargepressuregradientbetweenthenon-cavitatingpressuresideandthecavitatingsuctionsideenhancesthetipclearanceflows.Thecalculationconsideringthetipclearancereproducesthedevelopedcavitationregionsimilartothatofexperimentalvisualizations.Additionally,thebackflowcavitationrotateswiththespeedslowerthantherotationspeedoftheinducer.Then,therotationofbackflowcavitationcausestheperiodicfluctuationoftheoutletpressuregreaterthanthatoftheinletpressure.
