Chapter 7, moist Ai (第7章湿空气) 471 Introduction(介绍) 72 Properties of moist air(湿空气的参数) 473H- d Diagram of Moist Air(湿空气的H-d图) 7. 4 Thermodynamic Process of moist Air (湿空气的热力过程)
Chapter 7. Moist Air (第７章 湿空气） 7.1 Introduction (介绍) 7.2 Properties of Moist Air （湿空气的参数） 7.3 H-d Diagram of Moist Air （湿空气的H-d 图) 7.4 Thermodynamic Process of Moist Air （湿空气的热力过程）
71 Introduction(介绍) 空调、通风、烘干、冷却塔、储存 Atmospheric air 湿空气=(干空气+水蒸气) Dry air 理想混合气体 分压低 p=pat p 湿空气与一般理想混合气体的最大区别是:水蒸气的成分可 能变化
湿空气＝（干空气＋水蒸气） 空调、通风、烘干、冷却塔、储存 湿空气与一般理想混合气体的最大区别是：水蒸气的成分可 能变化。 理想混合气体 分压低 a v p p p = + Dry air Atmospheric air 7.1 Introduction (介绍)
1. Definition of Atmospheric Air(湿空气的定义) Dry air Water vapor(moisture) EAtmospheric Air (含有水蒸汽的空气称为湿空气。) Air that contains no water vapor is called dry air. (完全不含水蒸汽的空气称为干空气。) 2. Characteristics of Moisture Air(湿空气的特点) Atmospheric air contains a very small amount of water vapor. The partial pressure of water vapor is very low so that water vapor in the atmospheric air is always at superheated state Thus water vapor can be treated as ideal gas, (湿空气中水蒸汽含量很小,分压力很低,常处于过热状态,可以当 作理想气体来处理。)
1. Definition of Atmospheric Air（湿空气的定义） Dry air + Water vapor (Moisture) =Atmospheric Air (含有水蒸汽的空气称为湿空气。) Air that contains no water vapor is called dry air. (完全不含水蒸汽的空气称为干空气。) 2. Characteristics of Moisture Air (湿空气的特点) Atmospheric air contains a very small amount of water vapor. The partial pressure of water vapor is very low so that water vapor in the atmospheric air is always at superheated state. Thus, water vapor can be treated as ideal gas. (湿空气中水蒸汽含量很小，分压力很低，常处于过热状态，可以当 作理想气体来处理。)
Atmospheric air can be treated as a binary mixture(二元混合物) of ideal gases, dry air and moisture Dry air: Paav= marat Ra=83144l/289645=287.055J(kgK) Water vapor: pV=mdar t Rn=831441/1801528=461.520J/(kgK)
Atmospheric air can be treated as a binary mixture (二元混合物） of ideal gases, dry air and moisture Rda = 8314.41/28.9645 = 287.055 J/(kg·K) Rw = 8314.41/18.01528 = 461.520 J/(kg·K) Dry air: pdaV= mdaRdaT Water vapor: pwV= mdaRwT
3. Saturated Air and Unsaturated Air (未饱和空气和饱和空气) Superheated vapor过热蒸汽 Water vapor Saturated vapo饱和蒸汽 (1)未饱和湿空气( Unsaturated air) Dry air+ Superheated water vapor 干空气 T Unsaturated air p、未饱和湿空气 过热水蒸气 p、<Ps(T) 加入水蒸气,n
Saturated vapor 饱和蒸汽 (1) 未饱和湿空气(Unsaturated Air): Dry air+ Superheated water vapor Superheated vapor过热蒸汽 Water vapor 干空气 ＋ 过热水蒸气 pv < ps (T) T s pv ps 加入水蒸气，pv 3. Saturated Air and Unsaturated Air (未饱和空气和饱和空气) Unsaturated air 未饱和湿空气