Method
Moisture addition from dry-air mass flow and entering/target humidity ratios.
Equations
ṁw = ṁda · (W2 − W1)
Symbols and units
| Symbol | Quantity | Unit |
|---|---|---|
| Inputs | ||
| ṁda | Dry-air mass flow | kg/s |
| W1 | Entering humidity ratio | kg/kg dry air |
| W2 | Target humidity ratio | kg/kg dry air |
| Results | ||
| ṁw | Moisture added | kg/s |
| ṁw | Moisture added | kg/h |
Assumptions and limits
- Positive result denotes humidification; negative result denotes dehumidification.
Worked example
The input values are the calculator's own verification test, run through the calculator. They show the working; they are not design values.
Inputs
| ṁda | Dry-air mass flow | 1 kg/s |
| W1 | Entering humidity ratio | 0.008 kg/kg dry air |
| W2 | Target humidity ratio | 0.012 kg/kg dry air |
Results
| ṁw | Moisture added | 0.004 kg/s |
| ṁw | Moisture added | 14.4 kg/h |
A preliminary check for engineer review, not an engineering approval. The project calculation to the applicable codes, authority requirements and specification governs.