第1題Fluidisasubstancethat____?AcontinuestoexpanduntilthecontainerisfilledBisactuallyincompressibleCcannotwithstandshearstressDcannotremainstillundertheactionofanyshearforce第2題Incompressiblefluidreferstoafluidthatignores____?AdensityBdensityvariationCviscosityDchangesinviscosity第3題Whichofthefollowinggroupsofforcesbelongstomassforce____?ApressureandfrictionBgravityandpressureCgravityandinertiaforceDviscousforceandgravity第4題Inengineeringfluidmechanics,unitmassforcereferstothemassforceactingonaunit____?AareaBvolumeCmassDweight第5題Whenthepressureofwaterincreasesby1atmosphere,thedensityofwaterincreasesbyapproximately____?A1/20000B1/10000C1/4000D1/2000第1題Anincompressiblefluidcanbeconsideredtohaveadensityintheflowfield____?AincreaseswiththeincreaseofpressureBincreaseswithdecreasingpressureCdecreaseswithincreasingvolumeDisindependentofpressurechanges第2題Gasisafluidof____?AmobilityBcompressibilityCliquidityDmeasurability1.2.1ViscosityofFluid第1題ThefactordirectlyrelatedtoNewton'slawofinternalfrictionis____?AshearstressandpressureBshearstressandsheardeformationCshearstressandsheardeformationvelocityDshearstressandflowvelocity第2題Themaindifferencebetweenidealfluidandrealfluidis____?AliquidityBviscosityCgravitycharacteristicsDinertia第3題Theunitoffluiddynamicviscosityis()Am2/sBN/m2CN*sDPa*s第4題Whenthetemperatureofthesameliquidincreases,theviscosityoftheliquid____?AremainsBtendstozeroCdecreasesDincreases第5題WhichofthefollowingfluidbelongstoNewtonianfluid____?AWater,gasoline,alcoholBWater,freshconcrete,freshbuildingmortarCMudflows,mud,andplasmaDWater,waterstoneflow,naturalgas1.2.2Newtonianlawofinternalfriction第1題ThefactorsrelatedtoNewtonianinternalfrictionlaware____?Apressure,velocity,andviscosityBviscosity,shearstress,andangulardeformationrateCshearstress,temperature,viscosity,andvelocityDpressure,viscosity,andangulardeformation第2題AccordingtoNewtonianinternalfrictionlaw,themagnitudeofthefrictionalforceinsidethefluidisproportionaltothevelocitywhenthefluidflows.()1.3.1SurfaceTensionandCapillaryPhenomena第1題Whichofthefollowingforcesisnotasurfaceforce____?AinertialforceBviscousforceCpressureDsurfacetension第2題Amongthefollowingphenomena,whichoneismainlyaffectedbythesurfacetensionoftheliquid()AsewingneedlefloatsonthewatersurfaceBsmallwoodenboatfloatingonthewatersurfaceCcoinsfloatonthewatersurfaceDslowlypourwaterintothesmallglass,evenifthewaterlevelisslightlyabovetherim,thewaterwillnotflowout正確答案：ACD1.4ForcesactingonFluid第1題Thedensityofafluidisthe____perunitvolume?AmassBviscosityCpotentialenergyDkineticenergy第2題Unitbodyforcereferstothebodyforceactingonaunit____ofliquid?AareaBvolumeCmassDweight第3題Shearstressoffluid____?AdoesnotproducewhenthefluidisinastationarystateBduetocohesiveforces,itcangeneratewhenthefluidisinequilibriumConlydependsonthemomentumexchangeofmoleculesDonlydependsoncohesiveforce第4題Whichofthefollowingstatementsiscorrect____?AliquidcannotwithstandtensionorpressureBliquidcannotwithstandtension,butcanwithstandpressureCliquidcanwithstandtension,butcannotwithstandpressureDliquidcanwithstandbothtensionandpressure第5題Theviscosityofgasislow,anditdecreaseswithincreasingtemperature;theviscosityofliquidsishighanddecreaseswithincreasingtemperature.()2.1.1PressurePropertiesofStaticFluid第1題Gaugepressurereferstothedifferencebetweentheabsolutepressureatthatpointand____?AstandardatmosphericpressureBlocalatmosphericpressureCvacuumpressureDengineeringatmosphericpressure第2題Thelowerpartofasealedcontaineriswaterandtheupperpartisair.Theheightofthepressuremeasuringtubeat4.2mbelowtheliquidlevelis2.2m.Assumingthelocalatmosphericpressureis1engineeringatmosphericpressure,theabsolutepressureinsidethecontaineris____watercolumn?A2mB1mC8mD-2m第3題Theabsolutepressureatacertainpointisequalto0.4engineeringatmospheres,anditsrelativepressureis____?A0.6engineeringatmosphericpressureB-0.4engineeringatmosphericpressureC-58.8kPaD39.2kPa第4題Thedifferentialequationofhydrostaticpressureinthegravityfieldisdp=()A-ρgdzBρgdzC-(ρ/g)dzD(ρ/g)dz第5題Whenthegaugepressureatacertainpointisnegative,itindicatesthepresenceofvacuumatthatpoint.()2.1.2pressureatpoint第1題Afterbeingsubjectedtosurfacepressurep,aliquidwilltransfer____toanypointinsidetheliquid?AnotchangingatallBtherehasbeenanincreaseCreducedtosomeextentDonlytransmittingpressure第2題Theactualpressuremeasuredbythepressuregaugeisabsolutepressure.()2.1.2pressureatpoint第1題Afterbeingsubjectedtosurfacepressurep,aliquidwilltransfer____toanypointinsidetheliquid?AnotchangingatallBtherehasbeenanincreaseCreducedtosomeextentDonlytransmittingpressure第2題Theactualpressuremeasuredbythepressuregaugeisabsolutepressure.()2.2.1RelativeStaticLiquidinaNon-inertialCoordinateSystem第1題Thepressureperunitareainastationaryfluidiscalledthe____ofthefluid?AabsolutepressureBgaugepressureCstaticpressureDvacuumpressure第2題Forrelativeequilibriumoffluids____?AtheequalpressuresurfaceisnotorthogonaltothemassforceBisobaricsurfacecannotbeahorizontalsurfaceCtheshapeoftheisobaricsurfaceisrelatedtothedensityoftheliquidDtheinterfacebetweentwoliquidsisisobaric第3題Thepressurecalculatedstartingfromabsolutezeropressureiscalled____?AabsolutepressureBgaugepressureCstaticpressureDvacuumpressure第4題Theinternationalunitofstaticpressureforfluidis____?ANBPaCatmDbar第5題Thepressuredistributionwhentheliquidisinrelativeequilibriuminanuprightcontainerrotatingatequalangularvelocityis()Ap=p0+ρgh+12ω2r2Bp=p0+12ω2r2Cp=p0+ρghDp=p0?ρgh+12ω2r22.2.2Euler'sequilibriumequation第1題Staticfluiddoesnotshowviscosity.()第2題Foranequilibriumfluid,itssurfaceforceisthepressure.()2.3.1ForcesExertedonPlaneAreabyStaticLiquid第1題Themagnitudeofthehydrostaticpressureonaplanarwallofanyshapeisequaltothehydrostaticpressureat____multipliedbytheareaofthecompressionsurface?AcenterofcompressionsurfaceBcenterofgravityofcompressionsurfaceCthecentroidofthecompressionsurfaceDverticalcenterofcompressionsurface第2題Thegaugepressureatadepthof5minanopen-airpoolis____?A5kPaB49kPaC147kPaD205kPa第3題Whenviscosityisdisregarded,theforceexertedbyhydrostaticpressureonasurfacealwaysactsperpendiculartothesurface.()第4題Fromtheequilibriumdifferentialequationofstaticfluid,itcanbeinferredthatatmosphericpressuredecreaseslinearlywithincreasingaltitude.()第5題Thetotalstaticpressureonaplaneisequaltothepressureatthecentertimestheareaofthecompressedsurface.()2.3.2Forcesonsubmergedsurfaces第1題Therelationshipbetweenisobaricsurfaceandmassforceis____?AparallelBobliqueintersectionCorthogonalDirrelevant第2題Averticallyplacedrectangularflatplateisusedtoblockwater,withadepthof3m.Thedistancefromthethetotalstaticpressurecentertothefreesurfaceis____?A1.25mB1.5mC2mD2.5m第3題Thehorizontalcomponentofthetotalstaticpressureexertedbyastationaryliquidonacurvedsurface____?ApctheabsolutepressureatthecentroidofthecompressionsurfaceBpcrelativepressureatthecenterofpressureCAxtheareaofthecompressedsurfaceDAxtheprojectedareaofthecompressedsurfaceontheverticalplane2.4ForceExertedon2DCurvedSurfacebyStaticFluid第1題Thehorizontalcomponentofthetotalstaticpressureonacurvedsurfaceisequaltothetotalstaticpressureontheverticalprojectionsurfaceofthecurvedsurface.()第2題Thepointofactionofthetotalstaticpressureonacylindricalsurfaceisthecenterofthesurface.()2.5Buoyancy第1題Thebuoyancyofanobjectistheverticalcomponentofthetotalstaticpressureactingontheobject.()第2題Theaveragepressureonanycompressionsurfaceisequaltothepressureatthecentroidofthecompressionsurface.()3.1DescriptionofFluidMotion第1題UsingtheEulermethodtorepresenttheaccelerationofafluidparticleisequalto____?Ad2rdt2B?u?tC(u??)uD?u?t+(u??)u第2題TheLagrangianmethodiscommonlyusedinflowfieldstodescribeandanalyzethemotionofcontinuousmediumfluids.()3.2.1BasicConceptsforDescriptionofFluidMotion第1題ThemathematicaldescriptionofEulerdifferentialequationofmotionateachpointis____?AtheinletmassflowisequaltotheoutletmassflowBunitmassforceequalsaccelerationCtheenergydoesnotchangeovertimeDobeysNewton'ssecondlaw第2題GiventhatthevelocityfieldofanincompressiblefluidisV=x2zi+?2xyj,theflowbelongsto()Athree-dimensionalunsteadyflowBtwo-dimensionalunsteadyflowCthree-dimensionalsteadyflowDtwo-dimensionalsteadyflow第3題Steadyflowis____?AtheflowchangeswithacertainpatternovertimeBtheflowparametersateachspatialpointdonotchangewithtimeCthevelocitydistributionofeachcrosssectionisthesameDmigrationaccelerationiszero第4題Onedimensionalflowislimitedto____?AstreamlineisastraightlineBthevelocitydistributionchangesinastraightlineCtheflowparameterisafunctionofonespatialcoordinateandtimevariableDflowparametersdonotchangewithtime3.2.2PathLinesandStreamlines第1題Atthesamemoment,thevelocitydirectionofeachfluidparticlelocatedonthestreamlineisalwaysatthatpointandisconsistentwiththisstreamline____?AtangentBcoincidenceCparallelDintersection第2題Streamlinescanintersectorturn.()第3題TheLagrangemethodstudiesthemotionofindividualfluidparticlesatdifferenttimes,whiletheEulermethodstudiesthemotionoffluidparticlesatdifferentspatialpositionsatthesametime.()第4題PathlineandstreamlinearegeometricdescriptionsofLagrangianandEulermethods,respectively.Theyaredifferentexpressionsofthesamething,sopathlineisstreamlineandstreamlineispathline.()3.3.1FluidSystemandControlVolume第1題Asystemisacollectionoffluidparticlesthatalwayscontainthesamefluidparticlesandhaveadeterminedmass.()第2題Acontrolvolumereferstoaspecificspatialregioninaflowfield,wheretheshapeandpositionofthecontrolvolumeremainfixedrelativetotheselectedcoordinatesystem,andthefluidmassitcontainsmaychangeatanytime.()3.4.1EquationofContinuity第1題Withinaunitoftime,themassincrementcausedbydensitychangesinthecontrolvolumeisequaltothatfromthecontrolsurface____?AmassofinflowBmassofoutflowCthesummassofinflowandoutflowDthedifferenceinmassbetweeninflowandoutflow第2題Theamountoffluidflowingthroughanycross-sectionofapipelineperunittimeiscalled____?AvelocityBstreamlineCflowrateDstreamfunction第3題Thecontinuityequationrepresentstheconservationofmassofthecontrolvolume.()3.4.2derivativeofContinuityEquation第1題The____thatafluidflowsthroughinthedirectionofflowperunitoftimeiscalledthevelocity?AflowrateBheightCdistanceDline第2題Thecontinuityequationindicatesthatinsteadyflow,theaveragevelocityofflowisinverselyproportionaltothediameterofthecirculartube.()3.5.1KinematicDescription第1題Irrotationalflowlimitedto____?AstreamlineisastraightflowBpathlineisastraightflowCnonrotatingflowoffluidelementDsteadyflow第2題Ifthelineardeformationvelocityofthefluidiszero,thenthefluidisincompressible.()3.5.2derivativeofKinematicDescription第1題Iftheangulardeformationvelocityofthefluidiszero,thenthefluidisinirrotationalflow.()第2題Rotationalflowreferstothecircularmotionofafluid.()4.1.1MotionDifferentialEquationofIdealFluid第1題Eulerdifferentialequationofmotionforidealfluid____?AonlyapplicabletoincompressiblefluidsBonlyapplicabletocompressiblefluidsCapplicabletobothcompressibleandincompressiblefluidsDdependingonthespecificsituation第2題ThemathematicaldescriptionofEulerdifferentialequationofmotionateachpointis____?AtheinletmassflowisequaltotheoutletmassflowBunitmassforceequalsaccelerationCobeyNewton'ssecondlawDenergydoesnotchangeovertime4.1.2Euler’smotiondifferentialequation第1題()intheBernoulliequationrepresentsthepotentialenergyperunitmassoffluidAgzBu2/2Cp/ρDw第2題u2/2intheBernoulliequationrepresentsthe____perunitmassoffluid?ApotentialenergyBkineticenergyCstaticpressureenergyDeffectivework4.2.1BernoulliEquationandItsApplication第1題Variablediametertube,diameterd1=320mm,d2=160mm,flowvelocityv1=1.5m/s,v2is____?A3m/sB4m/sC6m/sD9m/s第2題Thevariationofthetotalheadlineofviscousfluidalongthewayis____?AdescendingalongthewayBascendingalongthewayCmaintainalevelDthreesituationsareallpossible4.2.2BernoulliEquationandItsApplication第1題Thevariationalongthepiezometricheadlineofaviscousfluidis____?AdescendingalongthewayBascendingalongthewayCmaintainalevelDthreesituationsareallpossible第2題()througheachpointontheuniformflowcrosssectionisequaltoaconstantApBz+pρgCpρg+u22gDz+pρg+u22g4.3.1MomentumEquation第1題Giventheratiod1/d2ofthediameterofthepipelinesectionbeforeandaftersuddenexpansion,theratiov1/v2oftheaverageflowvelocityofthecross-sectionbeforeandaftersuddenexpansion____?A4B2C1D0.5第2題Whensolvingproblemsusingmomentumequationwithatotalflow,____shouldnotbeincluded?AinertialforceBpressureCfrictionforceDgravity第3題Whichofthefollowingstatementsaboutwaterflowdirectionisincorrect()AwatermustflowfromhightolowBwatermustflowfromareaswithhigherflowvelocitytoareaswithlowerflowvelocityCwatermustflowfromareasofhighpressuretoareasoflowpressureDwatermustflowfromthehighheadofthepressuregaugetubetothelowheadofthepressuregaugetubeEwatermustflowfromcross-sectionareawithhighmechanicalenergytocross-sectionareawithlowmechanicalenergy正確答案：ABCD4.3.2ReynoldsTransportEquation第1題Themomentumequationcannotbeappliedto____?AtheflowofviscousfluidBunsteadyflowCbothoftheabovestatementsareincorrect第2題TheReynoldstransporttheoremisoneofthefundamentaltheoremsinfluidmechanics,whichdescribestheconservationpropertiesofmass,momentum,andenergyinfluidmotion.()第3題Whendividingthecontrolvolumeusingthemomentumintegralequation,thecontrolsurfacemustincludetheboundaryoftheentirefluidfield.()5.1.1SimilarityPrinciple第1題ThephysicalmeaningofReynoldsnumberis____?AtheratioofinertialforcetopressureBtheratioofinertialforcetogravityCtheratioofinertialforcetoviscousforceDtheratioofinertialforcetosurfacetension第2題ThedimensionofNewtonianinternalfriction[]is()AMLt?1BML?1t?2CML?1t?1DMLt?25.1.2NondimensionalizationofBernoulliequation第1題Thecorrectphysicalformulamustcomplywiththeprincipleofdimensionalharmony().()第2題ThedimensionlessΔP/ρVcomposedofphysicalquantitiessuchaspressureΔP,densityρ,andflowvelocityV.()5.2πLawandApplicationof第1題Ifthelinearscaleofthemodelis1:20,consideringviscosityasthemainfactor,thefluidinthemodelusedisthesameasthatintheprototype,andtheflowvelocityinthemodelis50m/s,thentheflowvelocityintheprototypeis()A11.1B1000C2.5D223第2題Ifthemagnitudeoftheforceswiththesamepropertiesactingonthecorrespondingpointsintwoliquidflowsisproportionalandinthesamedirection,thenthetwoliquidflowsaredynamicsimilarity.()第3題πtheorem,alsoknownastheBuckinghamtheorem,isatypeofdimensionalanalysismethod,andtheothersimplemethodistheRayleighmethod.()5.3.1NondimensionalizationoftheNSE第1題TheFroudenumbercanreflecttheratiooftheinertialforceofaliquidtoitsgravity.()第2題ThemainforceconsideredbytheReynoldssimilaritycriterionisviscousforce.()第3題TheimportanceofeachtermcanbedeterminedbydimensionlesstransformationoftheNavier-Stokesequation.()5.3.2ApplicationofDimensionalAnalysis第1題Thedimensionofunitbodyforceis()ALt?1BL?1t?2CLt?2DLt?1第2題Thedimensionofthedynamicviscositycoefficientis()AMLt?1BML?1t?2CML?1t?1DMLt?2第3題Ifthelinearscaleofthemodelis1:100,whichmeetsthegravitysimilaritycriterion,andthemodelflowvelocityis6m/s,thentheprototypeflowvelocityis()A600B0.06C60D600006.1ReynoldsExperiment第1題ThecriterionfordistinguishinglaminarandturbulentflowintheReynoldsexperimentis____?AthemagnitudeofReynoldsnumberBfluidvelocityCpipediameterDfluiddensity第2題WhichofthefollowingsituationswillincreasetheReynoldsnumber()AflowratedecreasesBthediameterofpipeincreasesCtheviscosityoffluidincreasesDfluiddensityincreases正確答案：BD第3題Theviscosityoffluidistherootcauseoffluidheadloss.()第4題Thefrictionheadlossisproportionaltothelengthoftheprocessandalsoproportionaltothediameterofthepipe.()6.2.1LaminarFlowinCircularPipe第1題Whenafluidflowsinahorizontalequaldiameterpipeline,theenergylossoftheflowis____?AthepressureenergygraduallydecreasesBkineticenergygraduallydecreasesCbothkineticenergyandpressureenergygraduallydecreaseDconservationofmechanicalenergy第2題Theparametersofeachpointintheflowfielddonotchangewithtime,onlywithspatialposition.Thistypeofflowiscalled____?AsteadyflowBunsteadyflowCnon-uniformflowDuniformflow6.2.2derivativeofLaminarFlowinroundPipe第1題Thefluidflowstateinacirculartubeisdividedintolaminarflowandturbulentflow.()第2題Theactualshearstressdistributionoflaminarflowinacircularpipeisalineardistributionwiththemaximuminthemiddleandzeroattheedgeofthepipewall.()6.3FrictionalLossinPipeline第1題Inturbulentroughpipezone____?AthelaminarboundarylayercoversaroughnessBthedragcoefficientalongthewaydependsonlyontheReynoldsnumberCheadlossalongthewayisproportionaltosquareoftheflowvelocityDthedragcoefficientalongthewayisindependentofrelativeroughness第2題AccordingtotheresultsoftheNikolazexperiment,whichofthefollowingiscorrect()Alaminarflowzoneλ=f(Re)Btransitionzonebetweenlaminarandturbulentλ=f(Re)Cturbulentsmoothzoneλ=f(Re)Dturbulenttransitionzoneλ=f(Re,Δ/d)Eturbulentroughzoneλ=f(Δ/d)正確答案：ABCDE6.4.1PipelineCalculation第1題Thelongpipeinhydrauliccalculationofpipelinesrefersto____?AverylongpipelineBpipelinewithsignificanttotalenergylossCpipelinewherelocallossescanbeignoredcomparedtoalongthefrictionlossesDpipelinethatcannotignorebothlocalandfrictionlosses第2題Intheseriespipelinesystem,theenergylossperunitmassoffluidineachbranchpipe____?AmustnotbeequalBthesumisthetotalenergylossperunitmassoffluidCmustbeequalDwhetherisequalornotdependsonwhetherthelengthsofthebranchpipesareequal6.4.2applicationofPipelineCalculation第1題Pressurelongpipelinesassumethatallwaterheadisconsumedinthefrictionlossesalongtheway.()第2題Theflowrateofeachsectionofaparallellongpipelinemustnotbeequal.()第3題Inhydrauliccalculationofpipelines,longpipesrefertopipesthatareverylong,whileshortpipesrefertopipesthatareveryshort.()第4題Theheadlossofeachsectionofaserieslongpipelinemayormaynotbeequal.()7.1.1DynamicdifferentialequationofviscousNSequation第1題TheNavier-Stokesequationisapplicabletodescribethemotionlawsofallviscousfluids.()第2題TheNavier-Stokesequationisadifferentialequationofidealfluidmotion.()7.1.2derivativeofNSequation第1題ThedifferencebetweenNavier-StokesequationandEulerdifferentialequationofmotionis____?Atheformerconsidersviscosity,whilethelatterdoesnotconsiderviscosityBtheformerdoesnotconsiderviscosity,whilethelatterconsidersviscosityCtheformerisformovingfluids,whilethelatterisforstationaryfluidsDtheformerisforstationaryfluids,whilethelatterisformovingfluids第2題Theassumptionofcontinuousmediumimplies____?AthefluidmoleculesaretightlyconnectedtoeachotherBthephysicalquantityoffluidisacontinuousfunctionCtherearegapsbetweenfluidmoleculesDthefluidisincompressible7.2.1Flowbetweentwoparallelplates第1題Incircularpipeflow,thecross-sectionalvelocitydistributionofturbulentflowconformsto____?AuniformLawBlinearvariationlawCparaboliclawDthelawoflogarithmiccurve第2題Incircularpipeflow,thecross-sectionalvelocitydistributionoflaminarflowconformsto____?AuniformLawBlinearvariationlawCparaboliclawDthelawoflogarithmiccurve7.2.2Axialflowbetweentwoconcentriccylinder第1題Whentheflowinacirculartubeislaminar,theresistancealongthepathisproportionaltothe____poweroftheaveragevelocity?A1B1.5C1.75D2第2題Whentheflowinacirculartubeislaminar,theaveragevelocityofitscross-sectionisequalto____timesthemaximumvelocity?A0.5B1C1.5D27.3ApproximateSolutionsoftheNavier-StokesEquation第1題Theplaneflowofincompressiblefluidsmusthaveapotentialfunction.()第2題TheNavier-Stokesequationsareanonlinearsystemofpartialdifferentialequations.()7.4BoundaryLayerApproximation第1題Thenecessaryconditionforboundarylayerseparationis

(coordinatesxalongtheflowdirection,yalongthenormaldirectionoutsidetheobjectplane)

?ABCD第2題Separationphenomenonofidealfluidflow____?AcannotbegeneratedBwillgenerateCwillgeneratewhenthesurfaceoftheflowingobjectchangesDdeterminewhethertherewillbeanyoccurrencebasedontheinflowsituationfinalexam-第1套第1題Fluidisasubstancethat____?AcannotremainstillundertheactionofanyshearforceBisactuallycompressibleCcanwithstandshearstressDcontinuestoexpanduntilthecontainerisempty第2題Incompressiblefluidreferstoaliquidthatneglects____?AdensityBchangesinviscosityCviscosityDdensityvariation第3題Whichofthefollowinggroupsofforcesbelongstomassforce____?ApressureBgravityandinertiaforceCgravityforceDviscousforce第4題Unitbodyforcereferstothemassforceactingonaunit____?ASurfaceareaBvolumeCweightDmass第5題Thedensityofwaterincreasesbyapproximately()withthepressureofwaterincreasing1atmosphereA1/1OOB1/20000C1/40000D1/20第6題Anincompressiblefluidcanbeconsideredtohaveadensityintheflowfield____?AdecreaseswithincreasingvolumeBincreaseswithdecreasingpressureCincreaseswithincreasingofpressureDisindependentofpressurechanges第7題Thelowerpartofasealedcontaineriswaterandtheupperpartisair.Theheightofthepressuremeasuringtubeat4.2mbelowtheliquidlevelis2.2m.Assumingthelocalatmosphericpressureis1engineeringatmosphericpressure,theabsolutepressureinsidethecontaineris()watercolumnA2mB1mC-2mD8m第8題Theabsolutepressureatacertainpointisequalto0.4engineeringatmospheresanditsrelativepressureis()A0.4engineeringatmosphericpressureB-0.6engineeringatmosphericpressureC39.2kPaD-58.8kPa第9題Thedifferentialequationofhydrostaticpressureinthegravityfieldisdp=()AρgdzB-ρgdzC-(ρ/h)dzD(ρ/h)dz第10題Thepressuredistributionwhenthefluidisinrelativeequilibriuminanuprightcontainerrotatingatequalangularvelocityis()Ap=p0?ρgh+12ω2r2Bp=p0+12ω2r2Cp=p0+ρghDp=p0+12ω2r2第11題UsingtheEulermethodtorepresenttheaccelerationofafluidparticleisequalto____?A?u?t+d2rdt2B?u?tC?u?t+(u??)uD(u??)u第12題WhichofthefollowingconceptsbelongtoEulermethod()AstreamlineBpathlineCfluidparticleDtwo-dimensionalsteadyflow第13題GiventhatthevelocityfieldofanincompressiblefluidisV=x2i+?2xyj,theflowbelongsto()Athree-dimensionalunsteadyflowBtwo-dimensionalunsteadyflowCthree-dimensionalsteadyflowDtwo-dimensionalsteadyflow第14題Thecontinuityequationrepresentsthe()conservationofthecontrolvolumeAenergyBmomentumCflowrateDmass第15題Itisknownthattheratioofthediameterofthesectionbeforeandafterthesuddenexpansionofthepipelined1/d2=0.5,thentheratiooftheaveragevelocityofthecorrespondingsectionv1/v2is()A8B4C2D1第16題Thecontrolvolumeis()AsystemofacertainmassBspacebodywithchangedpositionandshapeCfixedspacebodyDspacebodywithconstantshapeandmovingposition第17題Whenthemomentumequationisusedtocalculatetheresultantforceofthefluidontheobject,thepressureattheinletandoutletshouldbe()AabsolutepressureBgagepressureCatmosphericpressureDvacuumpressure第18題()intheBernoulliequationrepresentsthepotentialenergyperunitmassofliquidAwBu2/2Cp/ρDgz第19題Inengineeringfluidmechanics,thebasicdimensionis()AmassdimensionM,lengthdimensionL,timedimensionTBflowratedimensionQ,lengthdimensionL,timedimensionTCpressuredimensionP,lengthdimensionL,timedimensionTDstressdimensionP,lengthdimensionL,timedimensionT第20題Ifthegravityeffectoffluidisconsidered,whichsimilarityparametershouldbeconsidered()AFroudenumberBReynoldsnumberCEulernumberDMachnumber第21題Ifthelinearscaleofthemodelis1:20,consideringviscosityasthemainfactor,thefluidinthemodelusedisthesameasthatintheprototype,andtheflowvelocityinthemodelis50m/s,thentheflowvelocityintheprototypeis()A11B100C25D2.5第22題Thedimensionofunitbodyforceis()ALt?1BL?1t?2CLt?3DLt?2第23題Reynoldsnumberisanimportantdimensionlessnumbertodeterminewhichofthefollowingflowstate()AfastandslowflowBuniformflowandnon-uniformflowClaminarandturbulentflowDsteadyandunsteadyflow第24題Theshearstressdistributiononthecrosssectionoflaminarflowis()A