The contact factor of nozzles is defined as the efficiency for humidification. A 100% efficient nozzle
system will bring the moisture content of air to the saturation moisture content at the apparatus
dew-point, gc. The contact factor of the nozzle system can be defined by moisture content differences:
or by specific enthalpy differences:
The contact factor of a nozzle system depends on the design of nozzles, nozzle arrangement and water pressure.