air duct

tube

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Last updated

June 18, 2026

Quick Summary

An air duct is a tube used to convey air. This can be for ventilation in homes or ships, or to supply air to a furnace. Some fish also have an air duct connecting their air bladder to their alimentary canal.1

In the context of HVAC (Heating, Ventilation, and Air Conditioning) systems, air ducts are crucial for distributing conditioned air throughout a building. HVAC systems manage temperature, humidity, and air movement for comfort and safety in homes, businesses, and industrial settings. Modern systems often use a central unit, furnace, and fans to move air through ducts, controlled by a thermostat. Ventilation, a core HVAC function, relies on fans and ducts to bring in fresh air and remove stale air, sometimes manipulating air pressure for specific environments like hospitals.2

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sound
Acoustic filtration
…cross-sectional area are inserted into air ducts, as illustrated in Figure 3. The impedance mismatch introduced into a duct by a change in the area of the duct or by the addition of a side branch reflects undesirable frequencies, as determined by the size and shape of the variation. A…
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…cross-sectional area are inserted into air ducts, as illustrated in Figure 3. The impedance mismatch introduced into a duct by a change in the area of the duct or by the addition of a side branch reflects undesirable frequencies, as determined by the size and shape of the variation. A…
Read More