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Humidifier Calculation
2

Humidifier Calculation

Humidifier Calculation

(OP)
Can anyone help that How to calculate the Humidifier capacity (kg/hr) in accordance with the relevant CFM?
Please let me know, If there is any thumb rule like 400 CFM/ Tr for Cooling.

Eg.

The Air Flow is 6806
The Cooling Coil Air On Condition is 51.8 C / 20% RH
The Cooling Coil Air Off Condition is 14 C / 100% RH.

RE: Humidifier Calculation

Contact a humidifier mfg for this information.

RE: Humidifier Calculation

I would be fascinated to see how one can add humidity to a 100% RH saturated airflow. Perhaps some great new high technology...

RE: Humidifier Calculation

Since a dehumidifier operates on a refrigerant cycle, Perry chemical engineering handbook has a section showing calculations about the surface area of cooling coils based on CFM, RH in and out, temps of air and refrigerant in and out and their relating thermo. properties. The analysis also uses term found in psychrometry.

RE: Humidifier Calculation

As GMcD pointed out, your air is leaving the coil at a saturated condition. If this conditioned air enters a room where it warms up to 22°C, the relative humidity will become about 60%. Are you trying to achieve a higher %RH than that? Or should you be looking at leaving coil conditions during the heating season, which would be warmer and dryer?

Let us know what conditions you're trying to achieve in the room, and we might be able to help.

---KenRad

RE: Humidifier Calculation

If you want to actually understand how to calculate it, I recommend going to the ASHRAE Handbook of Fundamental, Chapter 6, Psychrometrics.

RE: Humidifier Calculation

(OP)
Dear urgross,
you have suggested the good thing to study about Humidifier Calculation.

RE: Humidifier Calculation

(OP)
If My Air Off Condition is 9 degree C and RH 30%, Can anyone please help me that how to calculate the humidifier Capacity (kg/hr)?

RE: Humidifier Calculation

(OP)
@KenRad,

Thank you for your valuable information.
I am looking for a heating condition.
If My Air Off Condition is 9 degree C and RH 30%, What will be my Humidifier Capacity?
Also could you please explain me how to calculate it?

RE: Humidifier Calculation

What is your desired indoor condition?
What is your sensible heat ratio?
Are you using steam?
Do you have a psychrometric chart?
Do you have a steam table?

RE: Humidifier Calculation

Most major manufactures offer selection software, For example https://www.armstronginternational.com/products-sy...
Most load software like HAP and Trace advise the moisture requirements for humdification.
Be careful with economizer operation and infiltration values. This sounds like a homework question. Look at the 2 points on a psy chart and the moisture delta.

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