Chemical Engineering - Mass Transfer - Discussion

WBT-AST = 0 only for air-water system (WBT=AST).

For other system, WBT>AST.

Wet bulb temperature is steady state non equilibrium temperature whereas adaibatic saturation temperature is equilibrium steady state temperature and so wet bulb temperature is greater than adaibatic temperature.

It is important to note that,

WBT-AST = 0 only for air-water system.....(WBT=AST).

For other system WBT>AST.

The Wet bulb temp is dew point at 100 % humidity (saturation temp).

For Humidities other than 100%, wet bulb temp and dew point are different. The temp difference is more than a fraction.

Wet Bulb temp is a means of detecting how saturated the air is. The larger the difference between wet & Dry bulb temp the dryer the air.

The dew point is the temp at which you must cool the current sample of air so that the partial pressure of water vapor contained in the sample equals the saturation pressure.

Wet bulb temp is always greater than dew point (adiabatic saturation temperature).