Issue with Buildings.Fluid.Humidifiers.Humidifier_u when mWat_flow_nominal is high

[Zoe-Lii]

I'm using Buildings.Fluid.Humidifiers.Humidifier_u, and found that when the humidifier’s mWat_flow_nominal exceeds the theoretical maximum moisture capacity of the air, and the heatPort is not connected, the temperature of the air passing through the humidifier will continue to go down after the relative humidity reaches 100%. As a result, the outlet air temperature of the humidifier will be lower than the inlet air's wet-bulb temperature.

Here is a simple way to reproduce the behavior.
-Inlet air situation:
Temperature: 5℃
Specific humidity: 1.347 g/kgda (which corresponds to a wet bulb temperature of -1.017 ℃)
-m_flow_nominal = 20 kg/s
-mWat_flow_nominal = 0.15 kg/s
Airflow:

Results:
The outlet air temperature should not be lower than -1.017℃; however, it is -13.53℃.

-Modelica Buildings Library: v11.0.0
-Modelica simulation environment: OpenModelica

I have added a calculation and judgment code to prevent this behavior. Before calculating the amount of water added to the air, I compare mWat_flow_nominal with m_air_flow * delta_Xi to ensure that the amount of water added to the air does not exceed the moisture capacity of saturated humid air. I’d like to know if there is a better way to solve this problem since I haven’t been using Modelica for long.

[mwetter]

Could you please upload the model that reproduces the issue.

Also note that Buildings.Media.Air is only valid for relative humidity not exceeding 100%, and treating the fog region would impact computing performance considerably (see info section of the media).