机械工程导论复习提纲.docx
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机械工程导论复习提纲
教2-323
Chapter1
1Whatisengineering?
Whatarethedifferencesbetweenengineeringandscience,mathematics?
2Howmanyfieldsisengineeringbrokedowninto?
3Which‘elements’areconcernedinthedisciplineofmechanicalengineering?
4Describedtheprofessionofmechanicalengineers.
5Describethecareerpathsofengineers.
6Describethemajorbranchesofmechanicalengineering.
7Describetheskillsthatanengineershouldhave.
8Whatproductordevicedoyouthinkshouldbeonthetopofmechanicalengineeringachievements?
Writeanapproximately200wordsreporttosupportyourviewpoint.
Chapter2
1Whatarethetwocomponentsofanengineeringquantity?
2WhatarethebaseunitsintheUSCSandSI?
3WhatareexamplesofderivedunitsintheUSCSandSI?
4HowaremassandforcetreatedintheUSCSandSI?
5Convertthefollowingquantitytotheothers.
1pound=newton(s)
1meter=feet(s)
1inch=millimeter(s)
1gallon=liter(s)
6Howshouldyoudecidethenumberofsignificantdigitstoretaininacalculationandreportinyourfinalanswer?
7Anumericalvalue10000has3significantdigits.Howtoexpressitclearlyandexplainit.
8Summarizethemajorstepsthatshouldbefollowedwhensolvingproblemstoclearlydocumentyourworkandcatchotherwiseavoidablemistakes.
9Thefollowingequationmeasurestheamountofresistancethatanobjectexperiencesasitmovesthroughairaroundit.
Here:
Dhastheunitsofforce,rofmassdensity,Aofarea,andvofvelocity.DeterminetheunitofCD.
10Makeanorder-of-magnitudecalculationtoestimatethecapacity,intheunitsofhorsepower,ofanelectricmotorthatwillpoweranelevatorinafour-storyofficebuilding.Theelevatorcarweighs500lb,anditwillcarryuptoanadditional2500lbofpassengersandfreight.
Chapter3
1TranslatethefollowingterminologyinmechanicalengineeringintoChinese.
Bearing,Journal,Rollingcontactbearing,Ballbearing,Straightrollerbearing,Taperedrollerbearing,Thrustrollerbearing,Flexibleshaftcoupling,Gear,Pinion,Spurgear,Involuteprofile,Diametralpitch,Rack,Bevelgear,Helicalgear,Wormgearset,Timingbelt,Chaindrive,Drillpress,Lathe,Mill,Leadscrew,Bolt,Washer,Nut,V-belt,Sheave,Synchronousrotation,Timingbelt,Chaindive,Machinetool,Massproduction,Drillpress,Lathe,Mill,Leadscrew,workpiece,Cuttingbit,CNCmill,Flatwasher,Springlockwasher
2Explainthedifferencesbetweenball,straightroller,taperedroller,andthrustbearings.Makethecross-sectionalshapesofthesebearings.
3Whatisthepurposeofabearing’sseparator?
4Explainthemethodthatassemblestheballsintotheracewaybetweeninnerandouterraces.
5Whatarethecharacteristicsofhelicalgears,andhowdotheydifferfromspurgears?
6Makeasketchtoexpressthegeometricparametersofarollingcontactbearing.
7Makesketchestoexpressthemethodthatusedinmechanicalengineeringdrawingsforscrewsorboltsandrollingcontactbearings.
8Whatisaleadscrew?
9Whatarethecharacteristicsofbeltandchaindrivesthataredifferentfromgearsets?
Chapter4
1WhataretheunitsforforceandmomentintheUSCSandSI?
2Howmanynewtonsareequivalentto1pound?
3Whyisasignconventionusedwhencalculatingmomentsusingthecomponentmethod?
4Whataretheequilibriumrequirementsforparticlesandrigidbodies?
5Whatarethestepsfordrawingafreebodydiagram?
6ThefollowingfigureshowsabeamsubjectedaforceofFonthefreeend.SketchaFBDtoanalyzetheforcesandmomentsoncross-sectionA.Drawthecurvestoillustratethemwiththehorizontalaxisofx.
7WhataretheunitsforfluiddensityandviscosityintheUSCSandSI?
8Makesketchestoillustratethedifferencebetweenlaminarandturbulentfluidflow.
9HowistheReynoldsnumberdefined?
10UseFBDtoexplainhowdoespressuregenerate.
11Giveexamplesofbuoyancy,drag,andliftforces,andexplainhowtheyarecalculated.
12Whatarethecoefficientsofdragandlift?
13WhatarethedefinitionoftheMachnumberinaerodynamics?
14WhatistheunitsofPoisefor?
15WhatisthecharacteristiclengthofReynoldsnumber?
Chapter5
1Whatisthedifferencebetweenelasticandplasticbehavior?
2Sketchstress-straincurvesforsteel,anddefinethefollowingterms:
elasticmodulus,proportionallimit,yieldpoint,andultimatepoint.
3Whatistheapproximatenumericalvaluefortheelasticmodulusofsteel?
4Anengineerdeterminesthata40-cm-longerrodof1020gradesteelwillbesubjectedtoatensionof20kN.Thefollowingtwodesignrequirementsmustbemet:
Thestressmustberemainbelow145MPa,andtherodmuststretchlessthan0.125mm.Determineanappropriatevaluefortherod’sdiameterinordertomeetthesetworequirements.Rounduptothenearestmillimeterwhenreportingyouranswer.
5Howistheyieldstrengthfoundusingthe0.2%offsetmethod?
6Inwhatwaysdotensileandshearstressesdiffer?
7HowistheshearyieldstrengthSsyrelatedtotheyieldstrengthSyobtainedfromatensiletest?
8Whatismeantbythetermfactorofsafety?
9Examplesintextbook:
5.1,5.2,5.3,5.4,and6.1.
Chapter6
1Howaregravitationalandelasticpotentialenergyandkineticenergy,calculated?
2Whatisthedifferencebetweenworkandpower?
WhataretheirconventionalunitsintheSIandUSCS?
3Whatisthe“heatofcombustion”ofafuel?
4Whatisthe“specificheat”ofamaterial?
5Explainhowheatistransferredthroughtheprocessofconduction,convection,andradiation.
6WhatisBTU?
Howisitdefined?
7Whatdothethreetermsontheleft-handsideoftheBernoulli’sequationrepresent?
Andverifyitisdimensionallyconsistent.
8Definethetermthermalconductivity.
9Whatarethefirstandsecondlawofthermodynamics?
10Whatisaheatengine,andhowisitsefficiencycalculated?
11WhatarethedifferencesbetweenactualandCarnotefficiencies?
12HowareabsolutetemperaturesdeterminedontheRankineandKelvinscales?
13Sketchthecrosssectionsoffour–strokeandtwo-strokeengines,andexplainhowtheywork?
14Whataretherelativeadvantagesanddisadvantagesoffour-strokeandtwo-strokeengines?
15Sketchablockdiagramofanelectricpowerplant,andexplainhowitworks.
Chapter7
1Whatisthedifferencebetweenaverageandinstantaneouspower?
2Howdosimpleandacompoundgeartrainsdiffer?
3Howarethevelocityandtorqueratiosofageartraindefined?
4Whatrelationshipexistsbetweenthevelocityandtorqueratiosforanidealgeartrain?
5Sketchaplanetarygeartrain,labelitsmaincomponents,andexplainhowitoperates.
6Whatisabalancedplanetarygeartrain?
7Describethemaincomponentsofanautomobiledrivetrain?
8Whatfunctiondoesthedifferentialinanautomobileserve?
9Sketchthepiston,connectingrod,andcrankshaftmechanisminaninternalcombustionengineorcompressor.
10Thefollowingfigureshowsacamandvalvemechanism.Thecanitselfiscircularwithradiusr=25mm,butitscenterCisoffsetfromtheshaft’scenterObye=10mm.Theshaftturnscounterclockwiseattheconstantspeed800rpm.(a)Determineanexpressionfortheverticalpositionxofthevalueasafunctionofthecam’srotationangleθ.(b)Differentiateyourresulttoobtainexpressionsforthevelocityandacceleration.(c)Whatarethemaximumvelocityandaccelerationofthevalve,andatwhatangleθofthecamdotheyoccur?
Chapter8
1Whatarethefourmajorstagesofthehigh-levelmechanicaldesignprocedure?
2Whatisthetechnologyof“rapidprototyping”?
3WhatarethemaincomponentsofaHydra-Matictransmission?
4IneachshiftofaHydra-Matic,howarethebrakesandclutchesset?
Chapter1
1Whatarethedifferencesbetweenengineering,scienceandmathematics?
2Howmanytraditionalcoredisciplinesdoesengineeringinclude?
3Whatarethedisciplineofmechanicalengineeringisconcerned?
Chapter2
1WhatareSIandUSCS?
WhatarethebasequantitiesandunitsinSIandUSCS,respectively?
2HowtodefinetheunitofmassinUSCS.
3Theconversionfactorbetweenfoot,inchandmeter,lbandNewton,kilogramandslug,etc.
4Whatisdimensionalconsistency?
ExpresstheBernoulli’sequationisdimensionalconsistency.
5Whatissignificantdigit?
Howmanysignificantdigitsdoes43.00have?
Howtoexpress2000lbwhenithas3significantdigits?
6Approximationinengineering:
estimatethepowerwhenyouclimbaflightofstairs.
Chapter3
1Bearing
Whatarerollingcontactbearingsandjournals,andthedifferencesbetweenthem?
Thestructureandcharacteristicsofball,straightroller,taperedroller,andthrustbearing.
Innerrace,outerrace,roller,separator
Radialforceandthrustforce.
2Gear
Thestructureandcharacteristicsofspur,rack,bevel,helical,andwormgears.
Thecross-sectionalshapeofthetoothofgear:
involuteprofile.
HowtomeasurethespacingbetweenteethofgearinSIandUSCS.
InSI:
m=2r/Nmodule
InUSCS:
p=N/2rdiametralpitch
Inorderforapinionandgeartobecompatible,theymusthavethesamevalueofdiametralpitchormodule.
3BeltandChain
Timingbelt
4MachineTools
Drillpress
WhatisCNCmill?
Chapter4
1Forcesandresultants
2Momentofaforce
3Equilibriumofforcesandmoments
Whatareparticlesandrigidbodies?
HowtosketchFBD(FreeBodyDiagram)?
UseFBDtosolvestaticproblem.
4Buoyancy
B=ρgv
5Dragforceandviscosity
Liquidorgasflowspastasphere(withdiameterd),thedragforceDopposesmotionis
D=3πμdv(Re<1)
μ--fluid’sviscosity.
Whatistheunitofμ?
Ca