Mechanical Engineering - Heat Transfer, Refrigeration and Air Conditioning - Discussion

The correct answer is: specific humidity.

During the humidification process, specific humidity increases. Specific humidity is the mass of water vapour per unit mass of dry air. When air is humidified, water vapour is added to the air, increasing the specific humidity.

Here's what happens to the other options during humidification:

- Wet bulb temperature (WBT): Remains constant or increases slightly.
- Relative humidity (RH): Increases.
- Dry bulb temperature (DBT): Decreases or remains constant.

Note that humidification involves adding moisture to the air, which increases the specific humidity. This process can be achieved through various methods, such as evaporative cooling, misting, or using humidifiers.

Specific humidity is an important parameter in psychrometrics, as it helps determine the air's moisture content and its potential for heat transfer and condensation.