When air, vapors, or light materials must be moved easily and inexpensively, air amplifiers provide a simple solution. These devices use the Coanda effect — the tendency of a fluid stream to be attracted to a nearby surface — to create air motion in their surroundings. Using a small amount of compressed air as their power source, air amplifiers pull in large volumes of surrounding air to produce high-volume, high-velocity outlet flows up to 25 times their consumption rate.

In one application, an automotive machine shop that manufactures disc brakes was having difficulty with chip buildup inside one of the parts. Flattened compressed air tubing didn’t solve the problem — it caused high sound levels, high compressed air use, and safety issues.

When compressed air tubing proved inefficient and ineffective at removing chip debris from machined parts, an air amplifier (pictured in the top right) from Exair Corp. was installed. It keeps parts debris-free while also reducing consumption of compressed air.

Replacing the tubing with a Model 120021 11⁄4 in. Super Air Amplifier from Exair Corp., Cincinnati, solved the problems. It provided a larger pattern of air, used less air, reduced noise, and couldn’t be dead-ended. In addition to the Super Air Amplifier, the company offers a variety of other models, including high-temperature and stainless-steel designs.

Compressed air flows through an air inlet (1), into an annular chamber (2). It then is throttled through a small ring nozzle (3) at high velocity. This primary airstream adheres to the coanda profile (4), which directs it toward the outlet. A low-pressure area is created at the center (5), inducing a high-volume flow of surrounding air into the primary airstream. The combined flow of primary and surrounding air exhausts from the air amplifier in a high-volume, high-velocity flow.

Air amplifiers offer maintenance-free operation as they have no moving parts. Flow, vacuum and velocity are easy to control, while outlet flows are easily increased by opening the air gap. Supply air pressure can be regulated to decrease outlet flow.

They offer a variety of advantages over other air blowing tools and devices — for example, unlike fans they do not require electricty or moving parts and offer no RF interference. When compared to venturis and ejectors, they also win out, because they provide more air flow with less compressed air consumption, higher flow amplification, no internal obstructions, and less noise.

Learn more about how air amplifiers work at www.exair.com or call (513) 671-3322.