Reply To: How to define boundaries when simulating relative humidity?

[Rob]

You need to set flow at one end or the other, so either velocity inlet or outlet, don't use both. If you're then spraying droplets into the system as these drop the temperature or evaporate you may get some non-physical RH values. You'd need phase mass transfer to condense material, that may not be worth the effort depending on what you're trying to find out.