




已閱讀5頁,還剩7頁未讀, 繼續(xù)免費(fèi)閱讀
版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進(jìn)行舉報(bào)或認(rèn)領(lǐng)
文檔簡介
-1-IntroductiontoMechanicalEngineeringMechanicalengineeringisthebranchofengineeringthatdealswithmachinesandtheproductionofpower.Itisparticularlyconcernedwithforcesandmotion.HistoryofMechanicalEngineeringTheinventionofthesteamengineinthelatterpartofthe18thcentury,providingakeysourceofpowerfortheIndustrialRevolution,gaveanenormousimpetustothedevelopmentofmachineryofalltypes.Asaresultanewmajorclassificationofengineering,separatefromcivilengineeringanddealingwithtoolsandmachines,developed,receivingformalrecognitionin1847inthefoundingoftheInstitutionofMechanicalEngineersinBirmingham,England.Mechanicalengineeringhasevolvedfromthepracticebythemechanicofanartbasedlargelyontrialanderrortotheapplicationbytheprofessionalengineerofthescientificmethodinresearch,design,andproduction.Thedemandforincreasedefficiency,inthewidestsense,iscontinuallyraisingthequalityofworkexpectedfromamechanicalengineerandrequiringofhimahigherdegreeofeducationandtraining.Notonlymustmachinesrunmoreeconomicallybutcapitalcostsalsomustbeminimized.FieldsofMechanicalEngineeringDevelopmentofmachinesfortheproductionofgoodsThehighmaterialstandardoflivinginthedevelopedcountriesowesmuchtothemachinerymadepossiblebymechanicalengineering.Themechanicalengineercontinuallyinventsmachinestoproducegoodsanddevelopsmachinetoolsofincreasingaccuracyandcomplexitytobuildthemachines.Theprincipallinesofdevelopmentofmachineryhavebeenanincreaseinthespeedofoperationtoobtainhighratesofproduction,improvementinaccuracytoobtainqualityandeconomyintheproduct,andminimizationofoperatingcosts.Thesethreerequirementshaveledtotheevolutionofcomplexcontrolsystems.Themostsuccessfulproductionmachineryisthatinwhichthemechanical-2-designofthemachineiscloselyintegratedwiththecontrolsystem,whetherthelatterismechanicalorelectricalinnature.Amoderntransferline(conveyor)forthemanufactureofautomobileenginesisagoodexampleofthemechanizationofacomplexseriesofmanufacturingprocesses.Developmentsareinhandtoautomateproductionmachineryfurther,usingcomputerstostoreandprocessthevastamountofdatarequiredformanufacturingavarietyofcomponentswithasmallnumberofversatilemachinetools.Oneaimisacompletelyautomatedmachineshopforbatchproduction,operationonathree-shiftbasisbutattendedbyastaffforonlyoneshiftperday.DevelopmentofmachinesfortheproductionofpowerProductionmachinerypresupposesanamplesupplyofpower.Thesteamengineprovidedthefirstpracticalmeansofgeneratingpowerfromheattoaugmenttheoldsourcesofpowerfrommuscle,wind,andwater.Oneofthefirstchallengestothenewprofessionofmechanicalengineeringwastothesteamturbineandassociatedlargesteamboilers.The20thcenturyhaswitnessedacontinuedrapidgrowthinthepoweroutputofturbinesfordrivingelectricgenerators,togetherwithasteadyincreaseinthermalefficiencyandreductionincapitalcostperkilowattoflargepowerstations.Finally,mechanicalengineersacquiredtheresourceofnuclearenergy,whoseapplicationhasdemandedanexceptionalstandardofreliabilityandsafetyinvolvingthesolutionofentirelynewproblems.Thecontrolsystemsoflargepowerplantsandcompletenuclearpowerstationshavebecomehighlysophisticatednetworksofelectronic,fluidic,electric,hydraulic,andmechanicalcomponents,alloftheseinvolvingtheprovinceofthemechanicalengineer.Themechanicalengineerisalsoresponsibleforthemuchsmallerinternalcombustionengines,bothreciprocating(gasolineanddiesel)androtary(gas-turbineandWankel)engines,withtheirwidespreadtransportapplications.Inthetransportationfieldgenerally,inairandspaceaswellasonlandandsea,themechanicalengineerhascreatedtheequipmentandthepowerplant,collaboratingincreasinglywiththeelectricalengineer,especiallyinthedevelopmentofsuitablecontrolsystems.-3-DevelopmentofmilitaryweaponsTheskillsappliedtowarbythemechanicalengineeraresimilartothoserequiredincivilianapplications,thoughthepurposeistoenhancedestructivepowerratherthantoraisecreativeefficiency.Thedemandsofwarhavechanneledhugeresourcesintotechnicalfields,however,andledtodevelopmentsthathaveprofoundbenefitsinpeace.Jetaircraftandnuclearreactorsarenotableexamples.BioengineeringBioengineeringisareactivelynewanddistinctfieldofmechanicalengineeringthatincludestheprovisionofmachinestoreplaceoraugmentthefunctionsofthehumanbodyandofequipmentforuseinmedicaltreatment.Artificiallimbshavebeendevelopedincorporatingsuchlifelikefunctionsaspoweredmotionandtouchfeedback.Developmentisrapidinthedirectionofartificialspare-partsurgery.Sophisticatedheart-lungmachinesandsimilarequipmentpermitoperationsofincreasingcomplexityandpermitthevitalfunctionsinseriouslyinjuredordiseasedpatientstobemaintained.EnvironmentalcontrolSomeoftheearliesteffortsofmechanicalengineerswereaimedatcontrollingmansenvironmentbypumpingwatertodrainorirrigatelandandbyventilatingmines.Theubiquitousrefrigeratingandair-conditionplantsofthemodernagearebasedonareversedheatengine,wherethesupplyofpower“pumps”heatfromthecoldregiontothewarmerexterior.Manyoftheproductsofmechanicalengineering,togetherwithtechnologicaldevelopmentsinotherfields,havesideeffectsontheenvironmentandgiverisetonoise,thepollutionofwaterandair,andthederelictionoflandandscenery.Therateofproduction,bothofgoodsandpower,isrisingsorapidlythatregenerationbynaturalforcescannolongerkeeppace.Arapidlygrowingfieldformechanicalandotherisenvironmentalcontrol,comprisingthedevelopmentofmachinesandprocessedthatwillproducefewerpollutantsandofnewequipmentandtechniquesthatcanreduceorremovethepollutionalreadygenerated.FunctionsofMechanicalEngineeringFourfunctionsofthemechanicalengineering,commontoallthefieldsmentioned,becited.Thefirstistheunderstandingofanddealingwiththebases-4-ofmechanicalscience.Theseincludedynamics,concerningtherelationbetweenforcesandmotion,suchasinvibration;automaticcontrol;thermodynamics,dealingwiththerelationsamongthevariousformsofheat,energy,andpower;fluidflow;heattransfer;lubrication;andpropertiesofmaterials.Secondisthesequenceofresearch,design,anddevelopment.Thisfunctionattemptstobringaboutthechangesnecessarytomeetpresentandfutureneeds.Suchworkrequiresnotonlyaclearunderstandingofmechanicalscienceandanabilitytoanalyzeacomplexsystemintoitsbasicfactors,butalsotheoriginalitytosynthesizeandinvent.Thirdisproductionofproductsandpower,whichembracesplanning,operation,andmaintenance.Thegoalistoproducethemaximumvaluewiththeminimuminvestmentandcostwhilemaintainingorenhancinglongertermviabilityandreputationoftheenterpriseortheinstitution.Fourthisthecoordinatingfunctionsofthemechanicalengineering,includingmanagement,consulting,and,insomecases,marketing.Inallofthesefunctionsthereisalongcontinuingtrendtowardtheuseofscientificinsteadoftraditionalorintuitivemethods,anaspectoftheever-growingprofessionalismofmechanicalengineering.Operationsresearch,valueengineering,andPABLA(problemanalysisbylogicalapproach
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 人人文庫網(wǎng)僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負(fù)責(zé)。
- 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。
最新文檔
- 深度剖析CAD工程師認(rèn)證試題及答案
- 2024年質(zhì)量風(fēng)險(xiǎn)分析框架試題及答案
- 2024焊接工程師考試內(nèi)容與試題及答案
- Adobe設(shè)計(jì)師考試環(huán)境與心理分析技巧試題及答案
- 三年級上冊心理健康教案-17《災(zāi)難面前要冷靜》 北師大版
- 2024智慧交通技術(shù)推廣與應(yīng)用試題及答案
- 2024年機(jī)械工程師資格考試學(xué)習(xí)資源的創(chuàng)新與優(yōu)化策略探討試題及答案
- 智慧交通產(chǎn)品市場前景試題及答案
- 初中化學(xué)人教版 (五四制)九年級全冊實(shí)驗(yàn)活動(dòng)2 一定溶質(zhì)質(zhì)量分?jǐn)?shù)的氯化鈉溶液的配制教案
- 焊接工程師證書考試壓力管理試題及答案
- NY∕T 309-1996 全國耕地類型區(qū)、耕地地力等級劃分
- 濃縮機(jī)的選擇與計(jì)算
- 滬教版六年級下冊單詞表
- 地基基礎(chǔ)軟弱下臥層驗(yàn)算計(jì)算表格
- 最新投標(biāo)書密封條
- SAPFI清賬接口和部分清賬接口例子
- TWI之工作改善JM精講
- 聚酯裝置流程與聚酯生產(chǎn)概述
- 鄉(xiāng)鎮(zhèn)綜治中心管理考核辦法(試行)
- BIM培訓(xùn)計(jì)劃Revit 培訓(xùn)計(jì)劃
- 中考英語常用特殊疑問句總結(jié)
評論
0/150
提交評論