Tag: coanda

Air Amplifiers – What is an Amplification Ratio?

Published on by Leave a comment

On Friday my colleague, Russ, blogged about the Super Air Amplifier (see that BLOG here, including a video demo)  In discussing the Air Amplifiers, the topic of amplification was mentioned. Today, I’d like to expand a bit further the amplification aspect of the Air Amplifier performance.

As the name of the device implies, the compressed air used by the Air Amplifier is added to, and thus ‘amplified’, the total output flow of the unit. Depending on the size and type of Air Amplifier, the amplification ratio starts at 12:1 and goes up to 25:1, with the ratio being the output flow to the compressed air usage.

AirAmplifiers.jpg
Super Air Amplifier and Adjustable Air Amplifier

EXAIR offers (2) types- the Super Air Amplifier and the Adjustable Air Amplifier.  The Super Air Amplifier uses a patented shim technology to maintain a precise gap, which controls the compressed air flow and expansion through the unit.  As the expanded air flows along the Coanda profile, a low pressure area is created at the center which induces a high volume flow of surrounding air into the primary air-stream.  The combined flow of primary and surrounding air exhausts from the Air Amplifier in a high volume, high velocity flow.  The larger diameter units have a greater cross sectional area with larger low pressure areas, resulting in greater amplification ratios.

The Below table shows the amplification ratios.

SuperAirAmplifierPerformance

The Adjustable Air Amplifier does not use a shim, but rather has an infinitely adjustable gap, allowing for fine adjustment of performance.  Force and flow is changed by turning the exhaust end to adjust the gap, and is then locked into place. The method of the amplification is the same as for the Super Air Amplifier, and the amplification ratios are similar and shown below.

AdjustableAirAmplifierPerformance

The Super Air Amplifiers and Adjustable Air Amplifiers are ideal for use in applications and processes that require cooling, drying and/or cleaning of parts, or the ventilation of confined areas or weld smoke or the exhausting of tank fumes.

If you have questions regarding the Air Amplifier, or would like to talk about any EXAIR Intelligent Compressed Air® Product, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

Send me an email
Find us on the Web 
Like us on Facebook
Twitter: @EXAIR_BB

What’s So “Super” About The Super Air Amplifier?

Published on by Russ BowmanLeave a comment
EXAIR Intelligent Compressed Air Products such as (left to right) the Air Wipe, Super Air Knife, Super Air Nozzle, and Air Amplifier are engineered to entrain enormous amounts of free air from the surrounding environment.

“Free air” from the surrounding environment?  You might think it’s too good to be true, and if you think you’re getting something for nothing, you’re right.  If you consider, though, that it’s oftentimes preferable to work smarter, not harder, then the use of engineered compressed air products is too good NOT to be true.  Case in point: the Super Air Amplifier.

The Coanda Effect is the “work smarter, not harder” part of the Super Air Amplifier

Simple and low cost, (hey, “engineered” doesn’t necessarily mean “complex and expensive”) the EXAIR Super Air Amplifier uses a small amount of compressed air to generate a tremendous amount of air flow through entrainment.  How much do they pull in?  Depending on the model, they entrain air at rates of 12:1 (for the 3/4″ Model 120020) to 25:1 (4″ & 8″ Models 120024 & 120028, respectively.)  The larger diameters mean there’s more cross sectional area to entrain air, so there is indeed efficiency to scale, size-wise.  There are a couple of great visuals in this video, if you want to see the entrainment in action (1:50) or the difference that the entrainment makes (1:30):

 

Where can you use a Super Air Amplifier?  The easy answer is, anyplace you want a consistent, reliable air flow.  The pressure supply can be regulated from a “blast to a breeze,” depending on the needs of your application.  The patented shim can be replaced for even higher performance, while maintaining the efficiency that makes it so valuable.  The balanced flow makes for incredibly quiet operation…no more noisy fans, blowers, or open-end compressed air pipes.  The body (3/4″ to 4″ sizes) is cast with a 2-hole flange for ease of installation.

When can you use a Super Air Amplifier?  Another easy answer: anytime you want.  If you need a continuous air flow, there are no moving parts to wear or electrical components to burn out.  Supply them clean, dry air, and they’ll run darn near indefinitely, maintenance free.

Alternately, if you need intermittent air flow, starting & stopping operation is as simple as opening & closing a valve in the compressed air supply line.  They produce rated flow immediately, and cut it off just as fast.

Some of the more popular applications are ventilation/exhaust, cooling, drying, cleaning, and dust collection.  There are five distinct models to choose from, and they’re all in stock.  We’re also happy to discuss special requirements that might lead to a custom product too.  Our Application Engineers work with Design & Production all the time to meet specific needs of particular situations.

If you’d like to find out more about letting the Super Air Amplifier, or any of EXAIR’s Intelligent Compressed Air Products work smarter for you, give me a call.

Russ Bowman
Application Engineer
Find us on the Web
Follow me on Twitter
Like us on Facebook

Video Blog: Which EXAIR Air Knife Is Right For You?

Published on by exaircorpLeave a comment

The following short video explains the differences between the 3 styles of Air Knives offered by EXAIR – The Super, Standard and Full-Flow. All of these Models are IN STOCK, ready to ship, with orders received by 3:00 PM Eastern.

If you need additional assistance choosing your EXAIR Air Knife, please contact an application engineer at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

 

EXAIR Blogs This Week Are Almost As Cool As Shark Week

Published on by Russ BowmanLeave a comment

Yes, ALMOST. This week, the EXAIR Blog has featured some excellent explanations of the science behind the operation of compressed air products. On Tuesday, John Ball posted the best explanation of SCFM vs ACFM that I’ve come across, and I’ve been explaining this to callers for almost four years now. I’m using his blog to perfect my “elevator pitch” on this topic. It will still likely require a building with more than ten floors, but I think that’s OK.

Also on “Two Blog Tuesday,” (this week only; I’m not trying to start anything) Dave Woerner’s gem of a blog detailed the terminology associated with pressure measurement, and why we use “psig” (g = gauged) – in a nutshell, the compressed air inside the pipe doesn’t care what the pressure outside the pipe is. And, since he mentioned it, I might add that most of agree that we care even less about how a certain NFL team’s footballs were (or were not) properly inflated.

Brian Farno’s “One Blog Wednesday” entry was a quite useful (if not alphabetical…OK; now I AM trying to start something) list of some common terms and expressions we use on a regular basis while discussing the operation and performance of EXAIR compressed air products. If you liked his photo demonstration of the Coanda effect with the foam ball & Super Air Amplifier, I encourage you to experience the Coanda effect for yourself, if you have access to a leaf blower and a volleyball:

I mention these earlier blogs to get to the point of MY blog today…a bit of theory-to-practice, if you will. Once you’ve gotten a decent understanding of these principles (or have the above links bookmarked for quick reference,) we can apply it to what’s needed for the proper operation of a compressed air product itself.

With a working knowledge of air flow (SCFM) and compressed air supply pressure (psig,) we can more easily understand why certain pipe sizes are specified for use with particular products. For instance, the longer the Super Air Knife and/or the longer the run of piping to it, the larger the pipe that’s needed to supply it:

This table comes directly from the Installation & Operation Instructions for the Super Air Knife.
This table comes directly from the Installation & Operation Instructions for the Super Air Knife.

The reasons for this are two-fold: First, the pipe…longer runs of pipe will experience more line loss (a continuous reduction in pressure, due to friction with the pipe wall…and itself) – so, larger diameter pipe is needed for longer lengths. For another practical demonstration, consider how much faster you can drink a beverage through a normal drinking straw than you can through a coffee stirrer. Not as dramatic as the leaf blower & volleyball (you really want to try it now, don’t you?) but you get my point.

Second, the Air Knife…the longer the Air Knife, the more air it’s going to use. And, if it’s longer than 18”, you’ll want to feed it with air at both ends…line loss will occur in the plenum as well.

In closing, I want to leave with another video, shot right here at EXAIR, showing the actual reductions in pressure due to line loss through different lengths, and diameters, of compressed air supply line to a Super Air Knife.

If you ever have any questions about compressed air use, or how EXAIR products can help you use your compressed air more efficiently, safely, and quietly, please give us a call.

Russ Bowman
Application Engineer
Find us on the Web
Follow me on Twitter
Like us on Facebook