Unit 36EngineeringThermodynamicsText Thermodynamicsisthestudyofthermalphenomena,thematerialsysteminequilibriumandtheestablishmentofthenatureoftherelationshipbetweenenergybalance,aswellasthestatechanges,thesystemofacademicinteractionwiththeoutsideworld. EngineeringthermodynamicsThermodynamicsisabranchofthefirstdevelopmentofitsmainresearchinheatandmechanicalenergyandotherenergyconversionbetweenthelawanditsapplicationinmechanicalengineeringisanimportantfoundationforonesubject. Thermodynamicsofthebasictasksoftheprojectis:throughthethermalsystem,heatbalance,heat,andthermalprocesses,andworkingfluid。thermodynamiccycleanalysis,improveandperfectheatengine,refrigeratorandheatpumpworkingcycle,toimproveenergyutilizationandheatconversionefficiency. Tothisend,thebasiclawofthermodynamicsmustbebasedonavarietyofthermodynamicpropertiesoftheprocess;studythethermalgasandliquidphysicalproperties,aswellasevaporationandcondensation,suchasphase-changerule;studyanalysisofsolutionpropertiesisnecessaryforcertaintypesofrefrigerator.ModernEngineeringThermodynamicsincludechemicalreactionssuchascombustionprocesses,suchasdissolvingthephysicalabsorptionordesorptionchemicalprocesses,whichalsoinvolvestheaspectsofchemicalthermodynamicsofbasicknowledge.Text EngineeringThermodynamicsisonthemacro-theoryofthermalphenomena,thestudyisamacro,ithasbeensummarizedbynumerousfactsofthefirstlawofthermodynamics,andthesecondlawofthermodynamicsthirdlawofthermodynamicsasabasisforreasoningbythematerialpressure,temperature,specificvolumeandothermacroparametersandheating,cooling,expansion,contraction,suchastheoverallbehaviorofthemacro-phenomenaandtostudythethermalprocess. Inthisway,theinternalstructureandmaterialtothespecificnature,asamacro-physicalpropertiesofrealdatatobesure,donotneedtomicro-structureofthematerialtomakeanyassumptions,soanalysisoftheresultsofreasoningwithahighdegreeofreliability,andcoherent.Thisisitsuniqueadvantages. Ancientmanlongagolearnedtomakefireanduseoffire,butthenpayattentiontoexplorethehot,coldrealphenomenon.However,untiltheendofthe17thcentury,peoplestillcannotcorrectlydistinguishbetweentemperatureandheatofthesetwobasicconceptsofnature.Popularatthattime,"saidHeatandMassTransfer"undertherule,peoplemistakenlybelievethatthehightemperatureobjectisstoredasaresultof"thermalmass"number.1709~Fahrenheittemperaturescalein1714and1742~1745Celsiustemperaturetoestablishthesubjecttomovethetemperaturewithacceptedstandards.TextFollowedbycalorimetrytechnologydevelopedforEarthobservationscienceandthermaltestingmeansisprovidedsothatthermalembarkedonthepathofmodernexperimentalscience. 1798,Langfordwasobserveddrillingwithdrillbarrel,theconsumptionofmechanicalworkandtheresultarewarmingbit.In1799,theBritishDavidwithtworesultinginfrictionbetweentheicesurfacemelting,whichisobviouslynotfromthe"HeatandMasssaid,"beexplained.1842,Meyermadetheconservationofenergytheory,thatheatisaformofenergycanbetransformedintomechanicalenergywitheachother,andtheairpressurefromthespecificheatcapacitywithconstantvolumespecificheatcapacitytocalculatethedifferencebetweenthemechanicalequivalentofheat. BritishphysicistJouleheatingintheequivalentin1840toestablishtheconceptin1842measuredindifferentwaysbeyondthemechanicalequivalentofheat.In1850,theexperimentalresultsofJoulehascompletelyabandonedthescientificcommunity,"HeatandMasssaid."Recognizedconservationofenergycanbeinterchangeableintheformoffirstlawofthermodynamicsfortheobjectivelawsofnature.EnergyunitJouleisnamedafterhim.Text Thermodynamicsoftheformationandpracticeatthetimetheproductionofanurgentneedtofindareasonablelarge-scale,highlyefficientheatengine-related.In1824,theFrenchoutofthefamousKanotheorem,theworkspecifiedinagiventemperaturerangetheheatengine'sefficiencycanreachthelimit,whichessentiallyhasestablishedthesecondlawofthermodynamics.However,bythe"heatandmasstransferthat"theimpactthathismethodsareprovenwrong.1848,BritishengineerKelvintheoremformulatedinaccordancewithCarnotthermodynamictemperaturescale.In1850and1851,GermanyandtheClausiusKelvinhasmadethesecondlawofthermodynamics,andonthisbasisre-provetheoremsKano. 1850~1854,accordingtoCarnottheoremClausiusproposedanddevelopedtheconceptofentropy.Firstlawofthermodynamicsandsecondlawofrecognition,fortwotypesof"perpetualmotionmachine"maketheimpossibletorealizethefinalconclusionsofscience,theofficialformationofthethermaltheoryofthermodynamicsofmacrophenomena.Atthesametimetheformationofthe"EngineeringThermodynamics"Thistechnologicalsciences,itbecamethestudyofheatengineworkingprincipleofthetheoreticalfoundationfortheinternalcombustionengine,steamturbine,gasturbinesandjetpropulsion,etc.havetomakerapidprogress.Text Atthesametime,researchintheapplicationofthermodynamictheoryofthenatureofthecoursematerial,butalsodevelopedthemathematicaltheoryofthermodynamics,thevarioussubstancesfoundinnaturetoreflectthecorrespondingthermodynamicfunctionwasstudiedinthephase-changematerial,chemicalreactionandthesolutionpropertiesfollowedbyavarietyoflaws.1906,GermanyNernstobservedphenomenaandchemicalreactionsatlowtemperaturefoundinheattheorem;in1912,thetheoremismodifiedintothethirdlawofthermodynamicsexpression. Sincethebeginningofthetwentiethcentury,ontheultra-highpressure,super-heatedsteamandotherphysicalproperties,andverylowtemperatureresearchtogainnewachievements.Withtheissueofenergy,andenergyofthecombinedcycle,anewtypeofcompositerefrigerantgreatresearchinterest.Thermodynamics n.熱力學(xué)Latentheat 潛熱Triplepoint 三相點Phase n.相Specificvolume 比體積Throttling n.節(jié)流State n.狀態(tài)Vacuum n.真空度Work n.功Wetsaturatedsteam

濕飽和蒸汽Wet-Bulbtemperature

濕球溫度Workingsubstance

工質(zhì)Evaporation

n.汽化System

n.系統(tǒng)

Boundary

n.邊界

Surrounding

n.外界

closed

system

閉口系統(tǒng)

open

system

開口系統(tǒng)NewWordsandPhrasesNotes（1）Thermodynamicsisthestudyofthermalphenomena,thematerialsysteminequilibriumandtheestablishmentofthenatureoftherelationshipbetweenenergybalance,aswellasthestatechanges,thesystemofacademicinteractionwiththeoutsideworld. 熱力學(xué)是研究熱現(xiàn)象中，物質(zhì)系統(tǒng)在平衡時的性質(zhì)和建立能量的平衡關(guān)系，以及狀態(tài)發(fā)生變化時，系統(tǒng)與外界相互作用的學(xué)科。（2）ModernEngineeringThermodynamicsincludechemicalreactionssuchascombustionprocesses,suchasdissolvingthephysicalabsorptionordesorptionchemicalprocesses,whichalsoinvolvestheaspectsofchemicalthermodynamicsofbasicknowledge. 現(xiàn)代工程熱力學(xué)還包括諸如燃燒等化學(xué)反應(yīng)過程，溶解吸收或解吸等物理化學(xué)過程，這就又涉及化學(xué)熱力學(xué)方面的基本知識。（3）Ancientmanlongagolearnedtomakefireanduseoffire,butthenpayattentiontoexplorethehot,coldrealphenomenon. 古代人類早就學(xué)會了取火和用火，不過后來才注意探究熱、冷現(xiàn)象的實質(zhì)。（4）In1799,theBritishDavidwithtworesultinginf