Psychrometric chart for the air-water vapor system

The humid volume of the air stream is determined by locating points F and G on the saturated and dry-volume curves, respectively, which correspond to 

Cy =heat capacity at constant volume, Btu/(lb)(°F) c = constant (see Table 2.1) 

Rs = relative saturation RFi = relative humidity T = temperature, °F tw = wet-bulb temperature, °F U = internal energy, Btu/lb 

1p = ratio of molal heat of vaporization to its normal boiling point. 

1 A mixture of vapor and liquid is in equilibrium. The density of the mixture is 0.99 lb/ft3. From the Steam Tables, determine the quality of steam for the conditions of 305°F and 72.2 psia. 

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