1、3 Vapor refrigeration cycles3.1 One-stage vapor compression systems3.2 Two-stage vapor compression systems3.3 Cascade vapor compression systems3.4 Vapor absorption systems 第三章 蒸汽制冷循环第一节 单级蒸气压缩制冷循环第二节 两级蒸气压缩制冷循环第三节 复叠式制冷循环第四节 蒸气吸收制冷循环2/28/202323 Vapor refrigeration cycles第三章 蒸汽制冷循环Vapor refrigeration
2、 cyclesRefrigeration cycles(Phase change)Gas refrigeration cyclesVapor compression cyclesVapor absorption cycles2/28/202333 Vapor refrigeration cycles第三章 蒸汽制冷循环Refrigeration cycles using pure refrigerantRefrigeration cycles(Component)Refrigeration cycles using mixed refrigerant3.1 One-stage vapor co
3、mpression systems3.1.1 Ideal cycles using pure refrigerants3.1.2 Practical cycles using pure refrigerants3.1.3 Practical cycles using mixed refrigerants 3.1.4 Analysis of cycles 第一节第一节 单级蒸气压缩制冷循环单级蒸气压缩制冷循环一、纯工质理论循环二、纯工质实际循环三、混合工质循环四、循环特性分析3.1 One-stage vapor compression systems3.1.1 Ideal cycles usi
4、ng pure refrigerants3.1.1.1 Saturated cycles3.1.1.2 Subcooled cycles3.1.1.3 Superheated cycles3.1.1.4 Recuperative cycles第一节第一节 单级蒸气压缩制冷循环单级蒸气压缩制冷循环一、纯工质理论循环（一）饱和循环（二）过冷循环（三）过热循环（四）回热循环2/28/20236Joule-Thomson effect and J.Perkins(1844,American)EvaporatorEtherCondenserCompressorExpansion valves2/28/2
5、02373.1 One-stage vapor compression systems 第一节 单级蒸气压缩制冷循环3.1.1 Systems using pure refrigerants 一、纯工质理论循环THTL4123TsOverheated corner2/28/202383.1 One-stage vapor compression systems 第一节 单级蒸气压缩制冷循环3.1.1 Systems using pure refrigerants 一、纯工质理论循环Overheated corner2/28/202393.1.1 Systems using pure refri
6、gerants 一、纯工质理论循环3.1.1.1 Saturated cycles（一）饱和循环Assumptions1.An isentropic compression2.No temperature diffidence3.Saturated liquid and vapor 4.No pressure loss2/28/2023103.1.1 Systems using pure refrigerants 一、纯工质理论循环3.1.1.1 Saturated cycles（一）饱和循环Energy balancesPartsCompressorCondenserExpansionEva
7、poratorFeaturesq0w0q0,w0w0Relationsw0h2-h1qkh2-h4h4h5q0h1-h5 qkh=q+w2/28/2023113.1.1 Systems using pure refrigerants 一、纯工质理论循环3.1.1.1 Saturated cycles（一）饱和循环IndexExpressionInfluence to cycle1q0q0h1-h5Gains2w0w0h2-h1Energy cost300q0/w0Energy cost4000/cEnergy cost5qkqkh2-h4Material cost6qvqvq0/v1Mater
8、ial cost7pkpkps(Tk)Material cost8p0p0ps(T0)Material cost9t2t2f(PR,k)Material cost10PRPRpk/p0Material costqkqk2/28/2023123.1.1 Systems using pure refrigerants 一、纯工质理论循环3.1.1.1 Saturated cycles（一）饱和循环IndexR134aR22R717Influence1q0128.5147.01043.1Gains2w042.646.59319.9Energy cost303.0163.1553.2610q0/w04
9、qv872.91595.91673.9Material cost5r0213219.51329qvq0/v16pk1016.41533.61555.5Material cost7p0132.7244.9190.18tc101.196133p0、pk9tf-96.6-160-77.910tb-26.1-40.76-33.311t248.467.6135.2Material cost12PR7.666.268.18t2t1(PR)(k-1)/k13k1.11.21.314Mol102.0386.4817.03k2/28/2023133.1.1 Ideal cycles using pure ref
10、rigerants 一、纯工质理论循环3.1.1.2 Subcooled cycles（二）过冷循环Assumptions 1.An isentropic compression2.No temperature diffidence 3.Subcooled liquid 4.No pressure loss2/28/2023143.1.1 Ideal cycles using pure refrigerants 一、纯工质理论循环3.1.1.2 Subcooled cycles（二）过冷循环IndexExpressionInfluence to cycle1q0q0 =h1 h4=h1 h4
11、q0 02w0w0 w 0w0=0300q0 /w0 0 Beneficial4000/c 0 5qvqvq0/v1 qv Beneficial2/28/202315 3.1.1 Ideal cycles using pure refrigerants 一、纯工质理论循环3.1.1.3 Superheated cycles（三）过热循环Assumptions 1.An isentropic compression2.No temperature diffidence 3.Superheated vapor 4.No pressure loss2/28/2023163.1.1 Ideal cyc
12、les using pure refrigerants 一、纯工质理论循环3.1.1.3 Superheated cycles（三）过热循环IndexExpressionsInfluence to cycle1q0q0q0q 0=02w0w0 w 0w 0 0300q0/w00 Harmful4000/c0 5q vq vq0/v1qv 2/28/2023173.1.1 Ideal cycles using pure refrigerants 一、纯工质理论循环3.1.1.4 Recuperative cycles（四）回热循环Assumptions 1.An isentropic compr
13、ession2.No temperature diffidence 3.Add a recuperative process 4.No pressure loss2/28/2023183.1.1 Ideal cycles using pure refrigerants 一、纯工质理论循环3.1.1.4 Recuperative cycles（四）回热循环IndexExpressionsInfluence to cycle1q 0q0=h1 h4=q0 q0 02w0w0 w 0w 0 0400q0/w0 0？Beneficial：R502、R290、R600a、R134aHarmful：R22、R7175000/c 0？3q vq vq0/v1 qv？2/28/2023193.1.1 Ideal cycles using pure refrigerants 一、纯工质理论循环3.1.1.5 Summary（五）小结过过冷冷循循环环过过热热循循环环饱饱和和循循环环回回热热循循环环2/28/202320Homework_1010.10.目前目前R22 R22、R134aR134a和和R717R717分别主要分别主要用在什么制冷装置中？为什么不同的用在什么制冷装置中？为什么不同的制冷装置要采用不同的制冷剂？制冷装置要采用不同的制冷剂？
