Chap. 1 SummaryEnergyTransferEnergyRelationshipstoTransformationsmatterpropertiesThermodynamicsApplicationareasZerothLawThe FirstLawCarnot PrinciplesTheSecondLawAScienceofEnergyTheIncreaseofetcEntropyPrincipleSystemClosed systemOpensystemThermodynamic SystemBoundary/SurroundingAdiabaticsystemIsolatedsystemAsetofpropertiesthatcompletelydescribestheconditionofthesystemStateEquilibrium:: Temperature(T), mechanical (P),phase, chemical State postulate: The state of a simple compressible system is completelyspecified bytwoindependentintensiveproperties.E.g.T(temperature)&v(specificvolume).orP&T (onephase)Isothermal,Isobaric,Path, CycleState 1 to State 2Isometric.IsoentropicQuasi-equilibrium:aprocessinwhichsystemremainsinfinitesimallyclosetoan equilibriumProcessstateaf alltimecReversible processSteadyflowprocessIreversibleprocessExtensivepropertiesV,E,H,SIntensive properties T.P,pPropertiesK273.15Triplepoint=0.01C=273.16K1Pascal=1N/m^2Pgage=Pabs - PatmPvac=Patm - Pabs
Chap. 1 Summary 1 Thermodynamics Energy Application areas A Science of Energy Thermodynamic System Zeroth Law The First Law The Second Law The Increase of Entropy Principle Carnot Principles etc Energy Transformations Relationships to matter properties Closed system Open system Isolated system Adiabatic system Intensive properties T, P, ρ Extensive properties V, E, H,S State State postulate: The state of a simple compressible system is completely specified by two independent, intensive properties. E.g. T(temperature)& ν (specific volume), or P&T (one phase) Equilibrium:: Temperature(T), mechanical (P), phase, chemical Path, Cycle Process State 1 to State 2 Steady flow process T K ℃ 273.15 Triple point=0.01℃=273.16K 1Pascal=1N/m^2 Pgage=Pabs - Patm Pvac=Patm - Pabs Transfer A set of properties that completely describes the condition of the system Properties Quasi-equilibrium: a process in which system remains infinitesimally close to an equilibrium state at all times. Isothermal, Isobaric, Isometric, Isoentropic Reversible process Irreversible process P System Boundary/Surrounding
Chap.2 SummaryTotal Energy, EIntermal Energy,UPotentialEnergy,PEKinetic Energy. KEEnergyForms of EnergyE=U+KE+PE=U+mV2/2+mgzMechanical energy,Nuclearenergy,Chemical Energy,SensibleenergyLatentenergy.Thermalenergy.Heat,Work,FlowworkConvectionTemperature diffBy Heat, QRadiationConductionEnergy Transfer, EForce*distanceBy Work, WForms ofwork:mechanical.shaft,spring,electrical,etcBy Mass, m=o,foraclosedsystemclosed systemQ=△U+ WEin-Eout=AEsystem1stLawofThermodynamicsEnergybalance:Ein-Eout=(Qin-Qout)+(Win-Wout)+(Emass,in-Emass,out)=EsystemEnergyChangeEffciency=desiredoutput/requiredinputEnergy Conversion EfficiencyCombustion efficiency.Overall efficiency,efficiency of generator, motor, pump, turbine, etc.福Energyand Environment
E=U+KE+PE=U+mV2 /2+mgz Chap.2 Summary 2 Forms of Energy Energy Transfer, E Total Energy, E Kinetic Energy, KE Potential Energy, PE Conduction Convection Radiation Effciency =desired output/ required input Ein-Eout= ∆Esystem Internal Energy,U 1st Law of Thermodynamics Energy balance: Ein-Eout=(Qin-Qout)+(Win-Wout)+(Emass,in-Emass,out)= ∆Esystem Energy Conversion Efficiency Energy and Environment Mechanical energy, Nuclear energy, Chemical Energy, Sensible energy, Latent energy, Thermal energy, Heat, Work, Flow work Energy By Heat , Q Temperature diff Forms of work: mechanical, shaft, spring,electrical, etc By Work, W Force*distance By Mass, m =0, for a closed system closed system Q=∆U+ W Energy Change: Combustion efficiency, Overall efficiency, efficiency of generator, motor, pump, turbine, etc
Chap.3 SummaryAsinglechemicalelementorcompoundAsubstancethat hasPure substanceHomogeneousmixtureofvariouschemicalelementsorcompoundsafixedchemicalcompositionmixtureoftwoormorephasesapuresubstanceCompressed liguid orsubcooled liquidliquidSaturated liquidSatruated liquid-vapor mixturePhase changeprocessSatruated vaporvaporSuperheatedvapor+Psat,Tsat,Latentheatoffusion/vaporization,sublimationsolidCritical pointSaturated liquid/vapor lineSuperheatedvaporregionT-v,P-v,P-T, P-v-T diagramsTripple pointCompressedliquid regionSaturated liquid-vapor region1Enthalpy/焰:acombinationpropertyh=u+Pv(kJ/kg);Entropy/PropertiestablesSaturated liguid/vaporormixture.ht,ha,haQualityx=[0.1]SuperheatedvaporCompressedliquid P,TReferencestatevalues1PV=RTPV=mRTR,RuIdeal gasequationofstateIdeal-gas/realgasZ=Pv/RTCompressibilityfactorReducedPReducedTequationofstateGeneralizedVanderwallsPrincipleofcorresponding statescompressibility chartequationofstate3
Chap.3 Summary 3 A substance that has a fixed chemical composition Phase change process A single chemical element or compound Enthalpy/焓: a combination property h=u+Pv (kJ/kg); Entropy/熵 Critical point T-v, P-v,P-T, P-v-T diagrams Properties tables Ideal-gas / real gas equation of state Pure substance liquid vapor solid Homogeneous mixture of various chemical elements or compounds mixture of two or more phases a pure substance Saturated liquid Satruated liquid-vapor mixture Satruated vapor Superheated vapor Compressed liquid or subcooled liquid Psat, Tsat, Latent heat of fusion/vaporization, sublimation Tripple point Saturated liquid/vapor line Superheated vapor region Compressed liquid region Saturated liquid-vapor region Saturated liquid/vapor or mixture. hf ,hg,hfg Quality x=[0,1] Superheated vapor Compressed liquid P, T Reference state/values Ideal gas equation of state Pv=RT PV=mRT R, Ru Compressibility factor Z=Pv/RT Reduced P Reduced T Principle of corresponding states Generalized compressibility chart Van der walls equation of state
Chap4 SummaryGeneral:Ow,=Pdy,P-VdiagramThework associatedBoundary workwithexpansionandIsobaricprocess,Pvn=const PolytropicprocesscompressionisothermalprocessofanidealgasW,=P,V,ln(V2/V)AE.(KJ)E-EouEnergyBalancesyatenNet enengy tnansferChange in intemal,kioctic.foranysystemandanyprocessbyhealwortandmasspoteatial,tc,enengis1stlawforclosedsystem=WWWWQ=Qnetin=0-0aet.ououtEnergyBalanceforclosedsystemO-W=AEThe energyrequired to raise T of 1kg ofa substanceby 1K,kJ/(kg.k)ahSpecific heatCv atconstant1Cp atconstantPCp22aTIdealgases:Cp=Cv+R;k=Cp/CvForsolidsand liquids,Cp=Cv=cU,h fromtable.Ah=h-hc,(T)dTepavg(T-T)Changes ofu, h for ideal gasesByusingCvorCpUsingaveragespecificheats.Cv,avg=Cv(T2/2+T1/2)Cp,avg=Cp(T2/2+T1/2)Forimcompressiblec(T)dT=Cav(T2-T)Ah=Au+VAPChanges of u,h for solid/fluidsubstances
Chap4 Summary 4 The work associated with expansion and compression 1st law for closed system General: δWb=Pdv, P-V diagram U,h from table. Specific heat Changes of u, h for ideal gases Changes of u, h for solid/fluid Boundary work Energy Balance for any system and any process Isobaric process, PVn=const Polytropic process isothermal process of an ideal gas Wb=P1V1ln(V2/V1) The energy required to raise T of 1kg of a substance by 1K, kJ/(kg.k) By using Cv or Cp Using average specific heats. Cv,avg=Cv(T2/2+T1/2) Cp,avg=Cp(T2/2+T1/2) Energy Balance for closed system Cv at constant V Cp at constant P Ideal gases: Cp=Cv+R; k=Cp/Cv For solids and liquids, Cp=Cv=C For imcompressible substances
Chap5 SummaryConservation of massprinciple:thenetmasstransfertoorfroma controlvolumeduringatimeintervalisequalto theConservationofmassnetchangeinthetotalmasswithinthecontrolvolumedmcvAmcmoutmindtoutinFlow energy:Totalenergyofaflowingfluidof1kg12(kJ/kg)Waow=PV=h+ke+pe=hgzEnergyofflowingfluid2V2Rate of energy transportE=mo=Igzm2V=大mMassbalanceIncompressibleOUDUinSingle streamPVA=PVA2nmSteadyflowProcess/systemV=V,-VA=VA2IncompressibleSinglestreamIFor△KE=0,△PE=0q-W=h2-hTurbines,compressorsNozzles,diffusersHeatexchangersSteadyflowdevicesPipeand ductflowThrottling valvesMixingchambers5
Chap5 Summary 5 Conservation of mass principle: the net mass transfer to or from a control volume during a time interval is equal to the net change in the total mass within the control volume. Energy of flowing fluid Nozzles, diffusers Steady flow Process/system Steady flow devices Conservation of mass Mass balance Flow energy: Total energy of a flowing fluid of 1kg Enthalpy is associated with the energy pushing the fluid into or out of CV Single stream Incompressible Incompressible Single stream Energy balance for general steady flow systems For For single stream △KE=0, △PE=0 Turbines, compressors Throttling valves Mixing chambers Heat exchangers Pipe and duct flow Rate of energy transport