Use

Determine the insertion loss due to a rectangular straight duct.

User Inputs

1. Width (mm)
2. Height (mm)
3. Length (m)
4. Lining thickness (mm) (from 0mm, 25mm or 50mm thickness with 24 kg/m$^3$ density).

SoundSurfer Input

Sound Power Level (red node) from an upstream source.

Algorithm

Insertion loss is based on Sound and Vibration Design and Analysis by National Environmental Balancing Bureau (NEBB) 1994:

• Section 5.2 Unlined rectangular sheet metal ducts
• Section 5.3 Acoustically lined rectangular sheet metal ducts

Tables 5.3, 5.5 and 5.6.