mechanicalengineeringAnintroductionto1Lecturer:LiuJu-rongCHAPTER1TheMechanicalEngineeringProfessionOVERVIEW1WHATISENGINEERING?23WHOAREMECHANICALENGINEERS?

2CAREERPATHS4TYPYCALPROGRAMOFSTUDY5Vocabulary3internalcombustionengine內(nèi)燃機(jī)roboticweldingequipment機(jī)械手焊接裝置prostheticlimb彌補(bǔ)性的，置換的，假肢jetengine噴氣式發(fā)動(dòng)機(jī)physicalquantity物理量trillionfold百萬兆（1012）autofocuslens自聚焦透鏡rowingmachine劃船機(jī)stairclimber爬樓梯機(jī)drillpress臺(tái)鉆Vocabulary4turbopump渦輪泵turbines汽輪機(jī)condenser壓縮機(jī)SpaceShuttle航天飛機(jī)robot機(jī)器人machinetool機(jī)床materialshandlingsystem物料搬運(yùn)系統(tǒng)industrialproductionequipment工業(yè)生產(chǎn)裝備accelerationsensor加速度傳感器1OVERVIEW----disciplineofmechanicalengineering5machinecomponentsforcesmaterialsenergymotiondesignWhat"elements”isconcernedinthedisciplineofmechanicalengineering?6FIGURE1.1Mechanicalengineersdesignandtestcomplexhighspeedmachinerysuchasthisdieselpowerplant（柴油機(jī)動(dòng)力裝置）forhighwayconstructionequipment．Source：ReprintedcourtesyofCaterpillarInc.1OVERVIEW---anexampleofmechanicalengineersdesign1OVERVIEW----mechanicalpowerrange710-3W103W106W109W1WAthleteAutomobileenginePowerplantWatt10-3hp103hp106hp1hpUltrasonicmotorMachinetoolsShuttlefuelpumpHorsepowerFIGURE1.2Mechanicalengineersworkwithmachinestheproduceorconsumepoweroveraremarkablywiderange8FIGURE1.3Close-upviewofaSpaceShuttlemainengineduringattestinwhichitisswiveledtoevaluatesteeringperformanceduringsimulatedflightconditions.

Source：ReprintedwithpermissionofNASA．1OVERVIEW----anexampleofmechanicalhighpower1OVERVIEW---Theabilitytobeavailableinthischapter9Afterstudy,whatshouldyoubeabletohave?Describethedifferencesbetweenengineersandscientistsandmathematicians.Describethetypeofworkthatmechanicalengineersdo,andlistsomeofthetechnicalissuesthattheyaddress.Discussthetypesofindustriesandgovernmentalagenciesthatemploymechanicalengineers.Listsomeoftheproducts,processes,andhardwarewithwhichmechanicalengineerswork.Describenotableachievementsofthemechanicalengineeringprofession.Understandthestructureandobjectivesofatypicalcurriculumformechanicalengineeringstudents.2WHATISENGINEERING?---Basicconcepts

Whatisengineering?

Whoisengineer?10ThewordengineeringderivesfromtheLatinrootingeniere,meaningtodesignortodevise,whichalsoformsthebasisofthewordingenious.Engineersapplytheirknowledgeofmathematics,science,materials,andphysicalprinciples--aswellastheirskillsincommunicationsandbusiness--inordertodevelopnewandbetterproductsandmachines.Ratherthanexperimentsolelythroughtrialanderror,anengineerdesignsfaster,moreaccurately,andmoreeconomicallybyusingmathematics,computers,andscienceasresources.112WHATISENGINEERING?---anexampleFIGURE1.4Aremarkableengineeringachievement,theSpaceShuttleAtlantisthundersintoorbitasitstwinsolidrocketboostersandthreemainenginesproduce7millionpoundsofthrust.

Source：ReprintedwithpermissionofNASA．2WHATISENGINEERING?----engineers’skillcombination12EngineeringScienceComputersimulationHardwareMathematicsFIGURE1.5Engineerscombinetheirskillsinmathematics,science,computers,andhardware.2WHATISENGINEERING?---traditionaldisciplines13mechanicalelectricalmaterialscivilchemicalthetraditionaldisciplinesofengineering2WHATISENGINEERING?----workingfieldsofengineers14FIGURE1.6Percentagesofengineersworkinginvariousengineeringfields.Allotherengineers28%Electricalandelectronics24%Mechanical15%Civil13%Industrial9%Aerospace4%Chemical3%Materials1%Petroleum1%Nuclear1%Mining1%3WHOAREMECHANICALENGINEERS?---definition15Theyalsodeveloppower-usingmachinessuchasrefrigerationandair-conditioningequipment,robotsusedinmanufacturing,machinetools,materialshandlingsystems,andindustrialproductionequipment.Mechanicalengineersresearch,develop,design,manufactureandtesttools,engines,machines,andothermechanicaldevices.Theyworkonpower-producingmachinessuchaselectricity-producinggenerators,internalcombustionengines,steamandgasturbines,andjetandrocketengines.16FIGURE1.7Robotsareextensivelyusedinautomatedindustrialassemblylinesandinmanufacturingapplicationsthatrequireprecisionwhenrepetitivetasksarebeingperformed,asintheassemblyandarcweldingoperationsshownhere.Source:ReprintedwithpermissionofFANUCRoboticsNorthAmericaInc.3WHOAREMECHANICALENGINEERS?---anexample17automobilesaircraftventilationimplantsreplacementheartvalvesequipmentfordetectingexplosivesroboticmanufacturingsystemsjetenginesThefieldofMechanicalEngineersmicroelectro-mechanicalcomputerharddrivesplanetaryexplorationandcommunicationsspacecraftdeep-searesearchvesselsair-conditioningsystemscellphonesheavyconstructionequipmentartificialhipheatingAccelerationsensors3WHOAREMECHANICALENGINEERS?---

-----workingfieldsofmechanicalengineers3WHOAREMECHANICALENGINEERS?---

---mechanicalengineering’smajorachievements181).Theautomobile2).TheApolloprogram3).Powergeneration4).Agriculturalmechanization5).Theairplane6).Integratedcircuitmassproduction7).Air-Conditioningandrefrigeration8).Computer-aidedengineeringtechnology9).Bioengineering

10).CodesandstandardsWhatisthemechanicalengineering'stopteninthetwentiethcentury?193WHOAREMECHANICALENGINEERS?----theautomobileFIGURE1.8Onaday-to-daybasis,mechanicalengineersusesophisticatedcomputer-aidedengineeringtoolstodesign,visualize,simulate,andimproveproductssuchastheautomobilesshownhere.Source:ReprintedwithpermissionofMechanicalDynamics,Incorporated.FIGURE1.9Mechanicalengineersdesign,test,andmanufactureinternalcombustionenginessuchasthiseight-cylinder5.7literengine.20FIGURE1.10AstronautJohnYoung,commander（指揮員）oftheApollo:16mission,leapsfrom（跳躍）thelunarsurfaceattheDescartesLandingsiteashesalutes（向...敬禮）theUnitedStatesflag.Therovingvehicle（探險(xiǎn)車）isparkedbesidethelunarmodule（登月艙）.3WHOAREMECHANICALENGINEERS?---

---theApolloprogramFIGURE1.11Artist’sconceptoftheInternationalSpaceStation.Source：ReprintedwithpermissionofNASA．213WHOAREMECHANICALENGINEERS?---

---PowergenerationFIGURE1.13Mechanicalengineersdesignrenewable(再生性能源)energysystems.Thewindfarmshownhereincorporatesseveral1-million-wattturbines.FIGURE1.12Thedesignforanadvancednuclearutilityplantcapableofproducing1billionwattsofelectricalpower.22FIGURE1.14Roboticvehiclesunderdevelopmentwillbeabletolearntheshapeandterrain(地形;地貌)ofafieldofgrainandharvestitwithessentiallynohumansupervision.3WHOAREMECHANICALENGINEERS?---

---AgriculturalmechanizationFIGURE1.15Agriculturalpluckingequipment.23FIGURE1.16TheairframeoftheF-22Raptorfighterisfabricatedfromaluminum,titanium,composites,andotheradvancedmaterialsinordertomeettheperformancedemandsoflowweightandhighstrength.Source：ReprintedwithpermissionofNASA．3WHOAREMECHANICALENGINEERS?---TheairplaneFIGURE1.17TheX-38researchvehicleisreleasedfromthewingpylonofitsmothershipduringaflighttest.Mechanicalengineerscontributetothetechnologiesneedforanemergencycrewreturnvehicle—orlifeboat—foruseonanorbitingspacestationandbasedontheX-38.Source：ReprintedwithpermissionofNASA．24FIGURE1.18Mechanicalengineersareinvolvedintheproductionofintegratedcircuitsandmicroprocessorsandinthedesignofthelithographymachines(光刻機(jī))thatmakesuchdevicesasthePentium4microprocessorshownhere.3WHOAREMECHANICALENGINEERS?---

---Integratedcircuitmassproduction253WHOAREMECHANICALENGINEERS?---

---

Air-conditioningandrefrigerationFIGURE1.19Air-ConditioningFIGURE1.20refrigeration263WHOAREMECHANICALENGINEERS?---

---Computer-aidedengineeringtechnology(examples)FIGURE1.22Contactstressanalysisofrollinggear(齒輪滾動(dòng)接觸應(yīng)力分析)FIGURE1.24rolling(軋制)FIGURE1.25Injectionmolding(注塑成形)FIGURE1.21Vibrationanalysisandexperiment(振動(dòng)分析與實(shí)驗(yàn))FIGURE1.23Thestampingprocessoftherearsuspensionspringbearingofacar(轎車后懸架彈簧支座沖壓過程)FIGURE1.26Movementofarmorpiercingfragments(穿甲碎片的運(yùn)動(dòng))27FIGURE1.27DrugfillingequipmentFIGURE1.28Nuclearmagneticresonanceapparatus3WHOAREMECHANICALENGINEERS?---Bioengineering4CAREERPATHS---responsibilityofmechanicalengineers28TechnicalexpertSystemsengineerEngineeringmanagerProgrammanagerMarketingstaffBusinessdevelopmentTechnicalsideBusinesssideAdvancedengineeringdegreesAdvancedbusinessdegreesFIGURE1.30Acontinuumoftechnicalandbusinessresponsibilitiesinengineering294CAREERPATHS---CareerladderEngineerSeniorengineerStaffengineerPrincipalengineerFellowProjectengineerEngineeringmanagerTechnicaldirectorTechnicalpathManagerialpathFIGURE1.28Potentialengineeringcareeropportunitiesinahypotheticalcompany.304CAREERPATHS---CommunicationskillsMechanicalengineersupervisors(監(jiān)理、主管),peers（同級(jí)、同輩）,customers,investors（投資者）,andvendors（供應(yīng)商）.Ateachstageofproductdevelopment,workwithco-workersdiscussandexplaintechnicalandbusinessconceptsclearlyandeffectivelyandtoworkwithandmotivateOtherswhoreadandusereports.documenttheirdesignsandtestresultsinwell-writtenreports5TYPYCALPROGRAMOFSTUDY---Generalrequirements31Asyoubegintostudymechanicalengineering,yourcollegeoruniversityprogramwillmostlikelyinclude：(4)electivecourses（選修課）onspecializedtopicsthatyoufindparticularlyinteresting.(3)asequenceofcorecourses（核心課程）inthefundamentalsubjectsthatallmechanicalengineersshouldknow;(2)preparatorycourses（預(yù)科課程）inmathematics,science,andcomputerprogramming;

(1)generaleducationcoursesintheareasofthehumanities,socialsciences,andthefinearts（美術(shù)）;5TYPYCALPROGRAMOFSTUDY---hierarchyofcourses32MechanicalengineeringDesignandmanufacturingMechanicalsystemsThermal-fluidengineeringMachinedesignComputerengineeringManufacturingsciencesThermo-dynamicsFluidmechanicsHeattransferStaticsSolidmechanicsDynamicsFIGURE1.31Hierarchyofcoursescompletedinatypicalmechanicalengineeringprogramofstudy.CorecoursesMajorbranches5TYPYCALPROGRAMOFSTUDY---Corecourses33Machineandproductdesign---conceivinganewdeviceanddesigningitindetail.Computer-aidedengineering---experiencewithcomputer-aideddesign,analysis,andmanufacturingtools.Manufacturingsciences--machiningprocesses,qualitycontrol,andproductiontechniques.5TYPYCALPROGRAMOFSTUDY---Corecourses34Dynamics--motionofmachinesandtheforcesthatareneededtomakethemmoveinadesiredmanner.Solidmechanics--stressesanddeflectionsofstructuralcomponentsandchoosingthematerialsfromwhichtheyaremade.Statics--understandingtheforcesthatactonmachinesandstructures.5TYPYCALPROGRAMOFSTUDY---Corecourses35Heattransfer---conduction,convection,andradiation,heatexchangers,insulation,andcoolingsystems.Fluidmechanics--physicalpropertiesofdifferentliquidsandgasesanddrag,lift,andbuoyancyforces.Thermodynamics--energyconservationandconversionandtheefficiencyofenginesandpower-generationmachinery.5TYPYCALPROGRAMOFSTUDY---Gainingexperience36

1.Anabilitytoapplyknowledgeofmathematics,science,andengineering.2.Anabilitytodesignandconductexperiments,aswellastoanalyzeandinterpretdata.3.Anabilitytodesignasystem,component,orprocesstomeetdesiredneeds.4.Anabilitytofunctiononmultidisciplinaryteams.5.Anabilitytoidentify,formulate,andsolveengineeringproblems.378.Thebroadeducationnecessarytounderstandtheimpactofengineeringsolutionsinaglobalandsocietalcontext.9.Arecognitionoftheneedforandanabilitytoengageinlifelonglearning.10.Aknowledgeofcontemporaryissues.11.Anabilitytousethetechniques,skills,andmodernengineeringtoolsnecessaryforengineeringpractice.6.Anunderstandingofprofessionalandethicalres