雨课堂学堂在线学堂云Experimental Fluid Mechanics(北京航空航天大学)单元测试考核答案

目录：Chapter1IntroductionChapter2TheoryofPhysicalSimilarityChapter3WindTunnelsChapter4ExperimentalModelsChapter5FlowMeasurementChapter6MeasurementUncertainty第1题WhatmethoddidMachusetodiscovertheshockwavephenomenoninsupersonicflight?ANumericalsimulationBTheoreticalderivationCExperimentalmethodDImagination第2题Whatprincipleisutilizedforastationarymodelinawind-tunnelbeingequivalenttoaflyingaircraftinair?AFlightprincipleBRelativityPrincipleofmotionCAircraftdesignprincipleDmeaurementprinciple第3题Whofliedthefirstpoweredaircraftintheworld?AWrightbrothersBF.H.WenhamCE.MariotteDB.Robins第4题Whatarethreemainbranchesoffluidmechanics?ATheoreticalFluidMechanicsBShipFluidMechanicsCExperimentalFluidMechanicsDComputationalFluidMechanics正确答案：ACD第5题whattechniquescontributetodevelopmentofexperimentaltechniques？ANumericalsimulationmethodsBNewsensorsCLaserDDataacquisition正确答案：BCD第6题Whatshouldweconsiderinanexperimentofaerodynamics?ARecordexperimenter'snameBSimulationofexperimentalconditionsCMeasurementofflowquantitiesDAnalysisofmeasurementerrors正确答案：BCD第7题DoesExperimentalaerodynamicsbelongtoExperimentalfluidmechanics第8题Robinsdesignedandconstructedthefirstwindtunnelintheworld.第9题Windtunnelsareroughlyclassifiedbyindustrialwindtunnelsandresearchwindtunnels.第1题Whichistheunitofvelocityinthefollowing?Akg/m3Bm/sCkg/ms2Dkg/ms第2题Howmanydimensionlessquantitiescanrepresentan+1quantities'systemifthereareKbasequantitiesinthePItheorem?An+1-kBn-kCn+kDn+1+k第3题Whichsimilarityparameterrepresentstherelationshipbetweenamomentumtransportationandheattransportation?AReynoldsnumberBMachnumberCStrouhalnumberDPrandtlnumber第4题Whichsimilarityparametersistheratioofconvectiveinertialtoelasticforce?AReynoldsnumberBMachnumberCStrouhalnumberDPrandtlnumber第5题Whichsimilarityparametersistheratioofconvectiveinertialtounsteadyinertialforce?AReynoldsnumberBMachnumberCStrouhalnumberDPrandtlnumber第6题Whichsimilarityparametersistheratioofconvectiveinertialtoviscosityforce?AReynoldsnumberBMachnumberCStrouhalnumberDPrandtlnumber第7题Whichofthefollowingsimilaritybelongtothephysicalsimlarity?AGeometricsimilarityBKinematicsimilarityCDynamicsimilarityDHeatsimilarity正确答案：ABCD第8题WhichofthefollowingequationsbelongtoNavier-Stokesequations?ABernoulliequationBMomentumequationCEnergyequationDContinuityequation正确答案：BCD第9题Whicharethebasicquantitiesinmechanics?ALengthLBNewtonNCTimeTDMassM正确答案：ACD第10题Whichsimilarityparametersarecommonlyusedinexperimentsoffluidmechanics?APrandtlnumberBReynoldsnumberCMachnumberDStrouhalnumber正确答案：ABCD第11题Whichofthefollowingexpressionsaretrue?Adiml=MBdimμ=L⁻¹MT⁻²Cdimu=LT⁻¹Ddimρ=L⁻³M正确答案：CD第12题Whatstepsareneededforderivingsimilarityparametersusingsimilaritytransformation?AListthegoverningequationsBListthesimilaritytransformationCSubstitutethetransformationintotheequationsDLetthecombinedquantitiesfromallscaleratiosareone正确答案：ABCD第13题Geometricsimilarityindicatesratiosofcorrespondingdimensionsbetweenaprototypeandamodelareequal.第14题Forsimilarityphenomena,therelationshipbetweenphysicalquantitiescanbeconvertedintotherelationshipbetweenthesimilarityparameters.ThisistheSecondSimilarityTheorem.第15题Basedongeneralfunctionrelationships,similarityparameterscanbeobtainedbyDimensionalAnalysis第16题Characteristicquantitiesarequantitieswithalldimensionindicesbeingzero.第17题Fortwophenomenaofphysicalsimilarity,thereexistdimensionlessquantitieswiththesamenumericalvalue,calledsimilarityparameters,whicharecomposedofcharacteristicquantities第18题Afterchoosingbasicquantities,listdimensionalmatrixanditsdeterminantmustbe0.Chapter3quiz第1题Whichwindtunnelcancoversubsonic/transonic/supersonicflowatatestsection?ADualspeedwindtunnelsBShockwindtunnelsCTriplespeedwindtunnelsDFreeflightwind-tunnels第2题Whichsituationcandecreaseenergylossinawindtunnel?AIncreasepressureBReducepressureCIncreaseairflowspeedDReduceairflowspeed第3题Whereisaexperimentalmodelinstalledinawindtunnel?ATestsectionBPowersectionCContractsectionDDiffuser第4题InaDeLavalnozzle,ifupstreamflowissubsonicanddownstreamflowissupersonic,whichstatementiscorrect?AdownstreampressuredecreaseBdownstreamTemperatureincreaseCdownstreamMa＜1DDownstreampressureincrease第5题WhichofthefollowingmeasuresdoesnotbelongtoQuiethypersonicwindtunnels?AHighlypolishedinternalwallofanozzleBGuidevaneincornersCBoundarylayersuctionatathroatDVerylongnozzletopreventGӧrtlerinstabilities第6题Whichtestdurationtimeisunreasonableinthecurrenthighenthalphyandhypersonicwindtunnels?A2hoursB1000secondsC10secondsD1millisecond第7题Whatconditionsdoesatestsectionneedtosatisfy?AHighcostBUniformspatialdistributionofvelocityCLowvelocityfluctuationDUniformspatialdistributionofvelocity正确答案：BCD第8题WhatareKeygeometricparametersforacontractionsection?AContractionratiosBInternalspaceCLengthDContourcurve正确答案：ACD第9题Whatarethecoolingapproachesforsubsonicwindtunnels?AliquidcoolingincornervanesoruseradiatorBExteriorwallcoolingCAirexchangecoolingDSmootherinteriorwall正确答案：ABC第10题Whatarethemaindifficultiesfortransonicwindtunnels,comparedwithsubsonicwindtunnels?AChokedflowinatestsectionBSubsonicwallinterferenceCShockreflectionDmanufacturecost正确答案：ABC第11题WhatquantitiesdomassflowreliesononceathroatreachesMa=1?AFlowvelocityBThroatareaCTotalpressureDTotaltemperature正确答案：ACD第12题Whatarethemaintypesofsupersonicwindtunnels?AHot-shotwind-tunnels(plasma)BContinuoussupersonicwindtunnelsCIntermittentsupersonicwindtunnelsDShockwindtunnels正确答案：BC第13题CryogenicwindtunnelisatypeofHypersonicwindtunnel.第14题Manumberwouldnotinfluencetheshapeofashockwave.第15题Inavarying-cross-sectionduct,airflowenergylossisproportionaltovelocitysquare.第16题Energyratioisameasureofeconomyofalow-speedwindtunnel.第17题Inanactualsituation,Ma=1generallyistheupperlimitofvelocityinsubsonicwindtunnels.第18题Aperforatedwallandplenumchamberaroundatestsectionareusedtoget0.8＜Ma＜1inatransonicwindtunnel.Chapter4quitz第1题Whichtypeofmodelisthebestforsimulatingtheintakeandexhaustofanengineofaircrat?ATurbofan-poweredsimulator(TPS)BSolidmodelwithmodifiedintakeandnozzleCFlow-throughmodelDSolidmodelwithanclosedintakeandnozzle第2题Inalow-speedandsubsonictesting,whatkindofmaterialistypicallyusedfordesigningamodel?ACeramicBAlloysteelCAluminumDpalstic第3题Whichofthefollowingoptionsarethesupportapproachesofanexperimentalmodel?ABottom-strutsupportBRear-stingsupportCWire-suspensionsupportDMagneticlevitationsupport正确答案：ABCD第4题Whatmotionformsofaircraftneedtobesimulatedusingadynamicdrivingmechanism?AUniformtranslationBPitchmotionCYawmotionDRollmotion正确答案：BCD第5题Forsupersonicexperiments,theratioofminimumcross-sectionareaofthemodeltotheareaofthetestsectionshouldbegreaterthanthetotalpressureratioofanormalshockinthetestsection.第6题Anoseconeatthefrontoftheinletandatailconeatthenozzleisasimpleapproachtosimulatetheintakeandnozzleofanengineinawindtunnel.第7题Theartificialtransitionshouldbeplacedata5%-10%chordlengthattheupperandlowersurfacesofawing.Chapter5quitz第1题Inastaticresponseofameasuringsystem,whatdoesthesmallestmeasurableinputrepresent?AResolutionBLinearityCDynamicrangeDStaticsensitivity第2题Whichkindoflinearsystemsdoesaresistorbelongsto?AZero-ordersystemBFirst-ordersystemCSecond-ordersystemDThird-ordersystem第3题Inordertomeasurecorrectsignals,atleasthowmanytimeshigheristhesamplingfrequencyofameasuringsystemthanthefrequenciesofthemeasuredsignals?AthreeBtwoCOneandahalfDone第4题Inthefollowingcomponentsofstrainbalance,whichonecandirectlysenseaerodynamicforcesandmoments?AElasticitypartBStraingaugeCWheatstonebridgecircuitDSignalconditioning第5题Inamarker-basedFlowvisualization,whichonerepresentsacurve,anypointofwhichistangenttoavelocityvectorinaflowfield?AIsobarBStreaklineCStreamlineDPathline第6题Inamarker-basedFlowvisualization,whichonerepresentsthemotiontrajectoryoffluidparticle?AIsobarBStreaklineCStreamlineDPathline第7题WhatshallwedotoprotectagainstexternalelectromagneticinterferenceAOperatewithoutElectro-StaticdischargeglovesBElectricalgroundingCShieldedcablefortransmittingmeasuredsignalsDShieldingsources正确答案：BCD第8题Whichonesbelongtoatypeofbalanceforforcemeasurement?AMechanicalbalanceBStraingaugebalanceCPiezoelectricbalanceDMagneticsuspensionbalance正确答案：ABCD第9题Whatarethebenefitsofaresonantpressuresensor?AStronganti-interferenceabilityBQuasidigitaloutputCTemperaturesensitiveDHighcost正确答案：ABD第10题Whenusingthelaserinducedfluorescence(LIF)methodbasedonanopticalmeasurementprinciple,whatwillinfluencefluorescenceintensity?AConcentrationBDirectionofmeasurementCTemperatureDPressure正确答案：ACD第11题Inadensity-basedFlowvisualization,whatmethodcanbeusedtovisualizeinformationofdensityanditsgradient?ASchlierenmethodBShadowgraphmethodCInterferometrymethodDWeatherglass正确答案：ABC第12题Liquid-columndifferentialpressuregaugebelongstoafirst-ordersystem.第13题Therelationshipthatconnectsthestaticinputasafunctionofthestaticoutputiscalledastaticresponseofthesystem.第14题Temperatureeffectsmustbetakenintoconsiderationwhendesigningastraingaugebalance.第15题Whenmeasuretheairflowtotal-temperature,astagnationtemperaturelossduetoaheatconductionandradiationshouldbetakenintoconsideration.第16题Turbulenceintensityisasimilarityparameter