Dew point temperature

dew point temperature

The dew point temperature is a limit temperature at which the air is 100% saturated with water vapour. At this point, no condensation occurs, nor can the air continue to hold water vapor.

When the temperature is lowered to a lower level, water is eliminated from the air by condensation.

An example is shown in the h,x diagram: If, for example, air with an absolute water content of x = 11 g/kg cools down from 30 °C to + 15 °C, the saturation line is reached.

A further cooling of the air leads to the elimination of condensate. The intersection of a vertical x-line with the saturation line is called the dew point and the corresponding temperature is called the dew point or saturation temperature

At dew point temperatures below the freezing point of water, the term frost or freezing point is also used.