工程热力学英文课件 sam5-双语学习资料

SAMChapter5

PropertiesofVaporandItsThermodynamicProcess水蒸气的性质及其热力过程工程热力学

EngineeringThermodynamicsSAM第五章水蒸气的性质及其热力过程

PropertiesofVaporandItsThermodynamicProcessKeynotesThermalEnergyEngineeringDepartment5-1§5-3水蒸气的热力过程

ThermodynamicProcessesofVapor§5-2水蒸气热力性质表和图

propertydiagramsandtablesofvapor§5-1水蒸气的发生过程

Theprocessofvaporgenerateing§5-1水蒸气的发生过程

TheProcessofVaporGeneratingSAMThermalEnergyEngineeringDepartment5-2H2O的p-T相图：临界点C(Criticalpoint)是汽液相变极限状态的标志。不同工质均有自己确定的临界参数，对水蒸气：三相点O:p0=0.6112kPa,t0=0.01℃,v0=0.001m3/kgabcde§5-1水蒸气的发生过程

TheProcessofVaporGeneratingSAMThermalEnergyEngineeringDepartment5-2未饱和水unsaturatedwater过热蒸汽superheatedvapor饱和水saturatedwater湿蒸汽saturatedmixture干饱和蒸汽saturatedvapor一、水蒸气的定压发生过程SAMThermalEnergyEngineeringDepartment5-3ab:preheatingprocess,

p=const,t,vchangesalittlebcd:Vaporizationprocess,p=const,ts

=const,vde:heatingofsaturatedvapor,p

=const,t,vchangesalittle液体热过冷度latentheatofvaporization

过热热量过热度汽化潜热SAMThermalEnergyEngineeringDepartment5-4干度若湿蒸汽可看成饱和水与干饱和水蒸气的混合物x=0saturatedwaterx=1saturatedvaporSAMThermalEnergyEngineeringDepartment5-7水蒸气定压产生过程会出现三个阶段和五种状态，且p↑→ts↑、v'↑、v"↓、汽化过程bd缩短。二、p-v,T-sdiagramof

vaporSAMThermalEnergyEngineeringDepartment5-6一点：临界点C二线：上界线BC、干饱和蒸汽线、x=1；下界线AC、饱和水线、x=0。三区：液态区、湿蒸汽区、汽态区。五态：未饱和水、饱和水、湿饱和蒸汽、干饱和蒸汽、过热蒸汽。SAMThermalEnergyEngineeringDepartment5-9§5-2水蒸气热力性质表和图

propertydiagramsandtablesofvapor国际水蒸气性质会议规定：取水的三相点（p=0.6112kPa,t=0.01℃）时饱和水的u0=0kJ/kg、s0=0kJ/（kg.K），则在压力不高时可近似的认为h0=0kJ/kg。水蒸气热力性质表饱和水及干饱和蒸汽表未饱和水与过热蒸汽表水蒸气热力性质图SAMThermalEnergyEngineeringDepartment5-10饱和水及干饱和蒸汽表（p124及附表p300-301）SAMSAMThermalEnergyEngineeringDepartment5-12未饱和水与过热蒸汽表表5-3未饱和水及过热蒸汽表的结构（p125）及附表12SAMSAMThermalEnergyEngineeringDepartment5-13SAMSAMThermalEnergyEngineeringDepartment5-14SAMSAMThermalEnergyEngineeringDepartment5-15SAMSAMThermalEnergyEngineeringDepartment5-15水蒸气热力性质图讨论（1）

已知H2O的（t,p）,如何确定其所处状态？（2）

已知H2O的（t,s）,如何确定其所处状态？SAMSAMThermalEnergyEngineeringDepartment5-15例5-2试确定压力为1MPa时，温度分别为160℃及200℃时水所处的状态。例5-3试用h-s图求下列状态的水蒸汽参数：（1）5MPa，干度＝90％；（2）温度为200℃的干饱和蒸汽；（3）0.1MPa，300℃。并将上述三个状态表示在h-s图上。例5-1若水蒸气在150℃时，比熵为6.0886kJ/(kgK)，试确定水蒸气的状态及其它状态参数。SAMSAMThermalEnergyEngineeringDepartment5-15例5-4(书上无)根据h-s图确定压力为2MPa时水蒸气的气化潜热的数值。SAMSAMThermalEnergyEngineeringDepartment5-15§5-3水蒸气的热力过程

ThermodynamicProcessesofVaporConstantVolumeProcessConstantTemperatureProcessConstantPressureProcessConstantEntropyProcessSAMSAMThermalEnergyEngineeringDepartment5-16例5-4某蒸汽锅炉，给水温度为150℃，出口蒸汽参数为3.5MPa，温度为435℃。试确定锅炉进、出口蒸汽的状态，并计算每千克水在锅炉内的吸热量。SAMSAMThermalEnergyEngineeringDepartment5-17例5-5一刚性容器中装有1kg汽水混合物，其中蒸汽质量占70％，压力为0.2MPa。若对容器加热，使水变成干饱和蒸汽，试求：⑴终态压力；⑵加入的热量；（3）终态温度。SAMSAMThermalEnergyEngineeringDepartment5-17例5-6假定从锅炉中输出的过热蒸汽（3.5MPa，435℃），在汽轮机中可逆绝热地膨胀