Terminal Units
The air terminal unit manages supply air from a central air handling station by controlling the volume and temperature of the air supplied to a space via the air diffuser. It is usually placed very close to the occupied space to offer better air control.
Ductborne Noise
![ExclamationMark_green_outline exclamation mark green icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2017/10/ExclamationMark_green_outline-80x80.png)
Problem
The throttling process in terminal units cause duct-borne noise. Some terminal units are fan powered and may add noise to the air stream. Since the terminal units are located relatively close to the occupied space, the duct-borne noise becomes an issue.
![Checkmark_green_outline checkmark icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2018/04/Checkmark_green_outline-80x80.png)
Solution
Silencers placed downstream of VAV boxes can attenuate the duct-borne noise generated by terminal boxes. Vibro-Acoustics analysis can determine the attenuation requirements off VAV boxes based on manufacturer’s data and room noise criteria.
Pressure Drop
![ExclamationMark_green_outline exclamation mark green icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2017/10/ExclamationMark_green_outline-80x80.png)
Problem
Maintaining a low pressure drop across Terminal boxes is critical to allow for effective air distribution. Catalogue selections may not take into account the system effect, thereby risk choking the system.
![Checkmark_green_outline checkmark icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2018/04/Checkmark_green_outline-80x80.png)
Solution
Silencers associated with Terminal units need to have very low applied pressure drops. Vibro-Acoustic systems approach takes into account the pressure drop with system effects.
Space
![ExclamationMark_green_outline exclamation mark green icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2017/10/ExclamationMark_green_outline-80x80.png)
Problem
Terminal boxes have space limitations since they are located relatively close to the diffusers. System effects may come into play for lack of duct lengths.
![Checkmark_green_outline checkmark icon](https://noisecontrol.vibro-acoustics.com/wp-content/uploads/2018/04/Checkmark_green_outline-80x80.png)
Solution
Vibro-Acoustics “Fit the duct” silencer philosophy takes into account the short run lengths and addresses them using extended casing silencers or elbow silencers.