Open Tank Evaporation 1

[Loumolito]

What is the resulting RH of air in a warehouse heated to 50-55F with a 35F open tank of water?

Knowns:
Building is 200x200
Open tank is 100x100
Ambient Outdoor 10F/20%RH
Indoor 50-55F
RH of Air?

 

[ChrisConley]

What is the application or process for the tank?

Is the water kept at 35F, or will it warm to ambient?
Airflow over the tank?

Hypothetically, with no dehumidification (closed system) the wetbulb of the space will eventually hit the temperature of the water.

 

[Loumolito]

The water temps will fluctuate based on groundwater temperatures. There is little air movement in the space.

I'm asked to evaluate the insulation properties of the enclosure to determine if condensation will occur.

So, if no outdoor air is introduced you think the Wet bulb of the space will reach the water temp?

 

[ChrisConley]

Basic mass diffusion. My guess in a real world application it won't get necessarily all the way there, but water will continue to evaporate into non-saturated air. I'd design for that scenario

 

[KiwiMace]

From the Psych chart, Saturation at 35degF will cause a worst case scenario of ~45%RH when heated up to 55degF. It will never get to this under these conditions.

This problem of yours is highly time dependent and needs to factor infiltration and ventilation to solve.

 

[willard3]

Have you measured the air velocity in the building?
That will influence the heat transfer most. If you have two different temperature heat sinks, you will have air motion.