直升机空气动力学介绍(英文版)VIP免费

©L.SankarHelicopterAerodynamics1HelicopterAerodynamicsandPerformancePreliminaryRemarks©L.SankarHelicopterAerodynamics2ThrustAeroelasticResponse027018090DynamicStallonRetreatingBladeBlade-TipVortexinteractionsUnsteadyAerodynamicsTransonicFlowonAdvancingBladeMainRotor/TailRotor/FuselageFlowInterferenceVNoiseShockWavesTipVorticesTheproblemsaremany..©L.SankarHelicopterAerodynamics3AsystematicApproachisnecessary•Avarietyoftoolsareneededtounderstand,andpredictthesephenomena.•Toolsneededinclude–Simpleback-of-theenveloptoolsforsizinghelicopters,selectingengines,layingoutconfiguration,andpredictingperformance–SpreadsheetsandMATLABscriptsformappingoutthebladeloadsovertheentirerotordisk–HighendCFDtoolsformodeling•Airfoilandrotoraerodynamicsanddesign•Rotor-airframeinteractions•Aeroacousticanalyses–Elasticandmulti-bodydynamicsmodelingtools–Trimanalyses,FlightSimulationsoftware•Inthiswork,wewillcovermostofthetoolsthatweneed,exceptforelasticanalyses,multi-bodydynamicsanalyses,andflightsimulationsoftware.•Wewillcoverboththebasics,andtheapplications.•Wewillassumefamiliaritywithclassicallowspeedandhighspeedaerodynamics,butnothingmore.©L.SankarHelicopterAerodynamics4PlanfortheCourse•PowerPointpresentations,interspersedwithnumericalcalculationsandspreadsheetapplications.•Part1:HoverPredictionMethods•Part2:ForwardFlightPredictionMethods•Part3:HelicopterPerformancePredictionMethods•Part4:IntroductiontoComprehensiveCodesandCFDtools•Part5:CompletionofCFDtools,DiscussionofAdvancedConcepts©L.SankarHelicopterAerodynamics5TextBooks•WayneJohnson:HelicopterTheory,DoverPublications,ISBN-0-486-68230-7•References:–GordonLeishman:PrinciplesofHelicopterAerodynamics,CambridgeAerospaceSeries,ISBN0-521-66060-2–Prouty:HelicopterPerformance,Stability,andControl,Prindle,Weber&Schmidt,ISBN0-534-06360-8–GessowandMyers–Stepniewski&Keys©L.SankarHelicopterAerodynamics6Grading•5HomeworkAssignments(eachworth5%).•Twoquizzes(eachworth25%)•Onefinalexamination(worth25%)•Allquizzesandexamswillbetake-hometype.TheywillrequireuseofanExcelspreadsheetprogram,oroptionallyshortcomputerprogramsyouwillwrite.•Allthematerialmaybesubmittedelectronically.©L.SankarHelicopterAerodynamics7InstructorInfo.•LakshmiN.Sankar•SchoolofAerospaceEngineering,GeorgiaTech,Atlanta,GA30332-0150,USA.•Website:www.ae.gatech.edu/~lsankar/AE6070.Fall2002•E-mailAddress:lsankar@ae.gatech.edu©L.SankarHelicopterAerodynamics8EarliestHelicopter..ChineseTop©L.SankarHelicopterAerodynamics9LeonardodaVinci(1480?1493?)©L.SankarHelicopterAerodynamics10HumanPoweredFlight?HP6.75.33/0.8MeritofrePower/FiguIdealPowerActual33.5A2WWPowerIdealslugs.0.00238Desnitysq.ft100AreaRotor6ft~RadiusRotor160lbfWeightHP©L.SankarHelicopterAerodynamics11D’AmeCourt(1863)Steam-PropelledHelicopter©L.SankarHelicopterAerodynamics12PaulCornu(1907)Firstmantoflyinhelicoptermode..©L.SankarHelicopterAerodynamics13DeLaCiervainventedAutogyros(1923)©L.SankarHelicopterAerodynamics14CiervaintroducedhingesattherootthatallowedbladestofreelyflapHingesOnlytheliftsweretransferredtothefuselage,notunwantedmoments.Inlatermodels,lead-laghingeswerealsousedtoAlleviaterootstressesfromCoriolisforces©L.SankarHelicopterAerodynamics15IgorSikorskyStartedworkin1907,Patentin1935Usedtailrotortocounter-actthereactivetorqueexertedbyt...