Reply To: how to input and get Relative Humidity in fluent?? – HVAC

[Rob]

RH is a function of the temperature and partial pressure of vapour. Partial pressure is a function of the mass fraction of vapour. You can set that.  Use Search as it's been discussed several times. 

Mass fraction is likely to remain constant over the domain. However, RH will vary assuming the temperature and pressure vary in the domain.