In the process of evaporation, sensible heat gets converted to latent heat.
Water vapor is at a higher energy level than liquid water. In order to evaporate, the activation energy must be overcome that is needed to provide the water molecules with the additional energy. This energy is taken out of the thermal domain.
In our model, humidity is used as an effort variable. It gets multiplied with a quantity that corresponds to the power converted in the process.
The humidity generated in the process of evaporation is proportional to the difference between the current humidity and the humidity at saturation vapor pressure, i.e., the humidity at the dew point.
Parameters: pao: Atmospheric pressure (default value = 87.848 kPa)
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