摘要
TheaimofthisstudyistoinvestigateexperimentallytheeffectofsurfaceroughnessoncloudcavitationaroundClark-Yhydrofoils.High-speedvideoandparticleimagevelocimetry(PIV)wereusedtoobtaincavitationpatternsimages(Prog.Aerosp.Sci.37:551–581,2001),aswellasvelocityandvorticityfields.ResultsarepresentedforcloudcavitatingconditionsaroundaClark-Yhydrofoilfixedatangleofattackofα=8?formoderateReynoldsnumberofRe=5.6×105.Theresultsshowthatroughnesshadagreatinfluenceonthepattern,velocityandvorticitydistributionofcloudcavitation.Forcavitatingflowaroundasmoothhydrofoil(A)andaroughhydrofoil(B),cloudcavitationoccurredintheformoffinger-likecavitiesandattachedsubulatecavities,respectively.TheperiodofcloudcavitationaroundhydrofoilAwasshorterthanforhydrofoilB.Surfaceroughnesshadagreatinfluenceontheprocessofcloudcavitation.ThedevelopmentofcloudcavitationaroundhydrofoilAconsistedoftwostages:(1)Attachedcavitiesdevelopedalongthesurfacetothetrailingedge;(2)Areentrantjetdeveloped,resultinginsheddingandcollapseofclusterbubblesorvortexstructure.Meanwhile,itsdevelopmentforhydrofoilBincludedthreestages:(1)Attachedcavitiesdevelopedalongthesurfacetothetrailingedge,withaccumulationandrotationofbubblesatthetrailingedgeofthehydrofoilaffectingtheflowfield;(2)Developmentofareentrantjetresultedinthefirstsheddingofcavities.Interactionandmovementofflowsfromthepressuresideandsuctionsidebroughtliquidwaterfromthepressuresidetothesuctionsideofthehydrofoil,finallyformingareentrantjet.Thejetkeptmovingalongthesurfacetotheleadingedgeofthehydrofoil,resultinginlarge-scalesheddingofcloudbubbles.Severalvorticesappearedanddissipatedduringtheprocess;(3)Cavitiesgrewandshedagain.
出版日期
2018年01月11日（中国期刊网平台首次上网日期，不代表论文的发表时间）
