What is a Super Air Amplifier

When I was working summers during school years I remember working in environments that were in unsatisfactory conditions. Since I was the the new kid and did not have seniority I had to take on the jobs that nobody wanted and therefore had the less than perfect working conditions. This company had a solvent welding process that at the time used Methyl Ethyl Ketone (MEK) as the bonding agent for ABS substrates. If only they knew about Air Amplifiers then! The solvent vapors on a hot humid Summer day would build up and I had to keep up with the quota while feeling a bit dizzy and disoriented! I couldn’t even run a fan as they were nervous blowing contaminants onto the substrates before going into the paint room. This is where a Super Air Amplifier could have helped.

Air Amplifiers are used for various reasons but in the story above could have been used for ventilation and keeping a safer work environment. Along with ventilating gasses/fumes these can be used for cooling hot parts, drying wet parts, cleaning machined parts, venting weld smoke, exhausting tank fumes, distributing heat within molds/ovens (circulation) and more! Super Air Amplifiers use the Coanda effect, a basic principle of fluidics, to create air motion. Using a small amount of compressed air as the source of power, the Super Air Amplifier then pulls in a large volume of surrounding air to produce high volume, high velocity outlet flows up to 25 times greater than the compressed air source.

Air Amplifiers use the Coanda Effect to generate high flow with low consumption.

Air Amplifiers have no moving parts making them virtually maintenance free to operate. No electricity is required. The flow, vacuum and velocity are easily controlled. Gross outlet flows can be adjusted by opening or closing the compressed air gap, which determines the amount of compressed air used. Supply air pressure can also be regulated to fine tune the outlet flow to meet application needs. Both vacuum and discharge ends of the air amplifier can be ducted, making them ideal for drawing fresh air from another location, or moving smoke and fumes away.

EXAIR carries a variety of sizes and styles and will even custom make Air Amplifiers for your every need. If you have questions about Air Amplifiers and want to talk to any of of many Application Engineers please contact us by calling 800.903.9247 or visit our website at www.EXAIR.com.

Eric Kuhnash
Application Engineer
E-mail: EricKuhnash@exair.com
Twitter: Twitter: @EXAIR_EK

How to Best Apply Vortex Tube Cooling

So, you have found yourself with a little bit of a conundrum. You need to cool a part but don’t know where to start and there are so many different options to choose from. In most cases when it comes to cooling with compressed air there are two different paths you can take. First is using a large volume of air at room temperature to blow across the surface area of the product. The other option is to use cold air from a vortex tube to drop the part’s temperature. In most case a large volume of air can be used to cool things down to relatively cooler temperatures; think cooling a cup of coffee using your breath. The issue you run into is when the temperature of the room air gets closer to the temperature you want to achieve in the end. In other words, when the temperature difference between your cooling air and your desired end temperature is small there is less cooling taking place with that same volume of air.

Mini Spot Cooler cooling down a bit used in milling plastic

This can be explained by looking at the cooling power formula:

Btu/hr = 1.0746*(CFM)*(Delta T)

In this case the Delta T is the difference between the temperature that you want to cool the product down to and the temperature of the air. This means the smaller the delta T is the higher the CFM flow will need to be to counteract the effect of the temperatures are so close to one another. Here are some examples of cooling a product and you are providing 1000 CFM of air to cool it.

Btu/hr = 1.0746*(1000 CFM)*(150F – 130F)

                Btu/hr = 21,492 Btu/hr

Btu/hr = 1.0746*(1000 CFM)*(150F – 100F)

                Btu/hr = 53,730 Btu/hr

As you can see the closer the Delta T is to 0 the less Btu/hr you get. Getting this kind of CFM flow is easy if you use something like EXAIR’s Super Air Knife or Super Air Amplifier. These systems take a small amount of compressed air and entrain the surrounding ambient air to increase the volume to a large blast. Take a look at model number 120022 which is the 2” Super Air Amplifier, this unit can produce 1,023 CFM while only using 15.5 CFM at 80 psig. But when you get close to cooling the temperature down to that room temperature or below it gets much harder; which only means that the temperature of the air being used to cool needs to be dropped. Dropping the air temperature can only be accomplished by using outside means like air coolers or in this case EXAIR’s Vortex Tubes and Spot Coolers.

EXAIR Air Amplifiers use a small amount of compressed air to create a tremendous amount of air flow.

Vortex Tubes and Spot coolers have some limitations. Generally they are not thought of products that produce large volumes of air (even though we make them up to 150 SCFM). And they are best suited for smaller areas of cooling, spot cooling, if you will. However, EXAIR Vortex Tubes do have one key feature that can help compensate for the lack of volume. LOW TEMPERATURE! The vortex tube can produce temperatures lower than 0F while stile retaining a good portion of air volume from the inlet.

Sub-zero air flow with no moving parts. 3400 Series Vortex Tubes from EXAIR.

For example, let’s look at model number 3240 running at 100 psig with 70% of the air from the inlet exiting the cold side (aka 70% cold fraction). At 100 psig the 3240 will use 40 SCFM at the air inlet and will have a temperature drop of 71F. If the compressed air has a temperature of 70F that means you will be seeing a temperature of -1F. Also, when using the 70% cold fraction you will see 28 SCFM of cold air flow. Now let’s plug those numbers into the cooling power formula.

 Btu/hr = 1.0746*(28 CFM)*(150F + 1F)

                Btu/hr = 4543 Btu/hr

As you can see, using a small amount of compressed air you can still net you a good amount of cooling if the temperature is lower. All in all, the best option for cooling products down to temperatures that are above ambient temperatures is something that can produce a large volume of air. For small areas that require cooling the product down to temperatures to ambient temperature and below, use EXAIR’s Vortex Tube.

If you have questions about our Air Amplifiers and Vortex Tubes, or would like to talk about any of the quiet EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR or any Application Engineer.

Cody Biehle
Application Engineer
EXAIR Corporation
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Super Air Amplifiers: Evacuation of Smoke or Fumes

Air Amplifiers Are Great For many things!

In the pneumatic industry, there are two types of Air Amplifiers.  One type will amplify the inlet air pressure to a higher pressure.  The other type uses the inlet air pressure to amplify the air volume.  EXAIR manufactures the volume type called the Super Air Amplifiers™. 

This change in air volume is called the amplification ratio.  So, what does this mean?  The definition of ratio is the relation between two amounts showing the number of times one value is contained within the other.  For the EXAIR Super Air Amplifiers, the ratio is the value that shows the amount of ambient air that is drawn within the compressed air.  The higher the ratio, the more efficient the blowing device is.  The EXAIR Super Air Amplifiers can reach amplification ratios up to 25 to 1.  This means that 25 parts of ambient “free” air is introduced for every 1 part of compressed air. 

Why an EXAIR Super Air Amplifier?  Like a fan, they are designed to move air.  But fans use motors and blades to push the air toward the target.  The fan blades “slap” the air which creates turbulent air flows and loud noises. The Super Air Amplifiers do not use any blades or motors to move the air.  They just use a Coanda profile and a patented shim to create a low pressure to draw in the ambient air.  In physics, it is much easier to pull than it is to push.  The process of pulling air through the Super Air Amplifiers make them a more efficient, uniform, and quiet way to blow air.    

Super Air Amplifier – flow region

To show the power of the Super Air Amplifier, we have a video of a model 120022.  In the video, oil is being heated to generate smoke, and the Super Air Amplifier is placed in the center of an exhaust pipe.  This demonstration was for a customer that was looking to evacuate vapors from an enclosed area.  Other applications would include welding smoke, ventilation, exhaust tank fumes, and dust collection.  You can see when the Super Air Amplifier is turned on and in operation in the video below. 

EXAIR manufactures and stocks five different sizes ranging from ¾” (19mm) up to 8” (203mm) in diameter.  Some of the benefits that the Super Air Amplifiers have is the inlet and outlet can be ducted for remote positioning.  They are very compact and can fit into tight places like the exhaust pipe above.  They do not have any moving parts to wear or need electricity to run.  They only need clean compressed air to operate; so, they are maintenance-free.  Another unique feature of the EXAIR Super Air Amplifier is the patented shim which optimizes the low-pressure to draw in more ambient air.   As an added bonus, they are OSHA safe and meet the standards for noise level and dead-end pressure. 

With the today’s cost to make compressed air, it is important to use it as efficiently as possible.  The EXAIR Super Air Amplifiers have the ability to give effective blowing to remove debris, dry parts, transport material, cool objects, and clear smoke without using a large amount of compressed air.  EXAIR has the Super Air Amplifiers in stock and as always, EXAIR offers a 30-day unconditional guarantee for our customers in the U.S. and Canada to try them out.  If you have any questions about the Super Air Amplifiers or if you would like to discuss your application, an Application Engineer at EXAIR will be happy to help you.

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Thinking Outside of the Box

Over the years of working at EXAIR, I have spoken to thousands of customers. The applications we discuss can run the full range that is showcased in the Solutions section of our website. It is always fun to approach applications when we have to think outside of the box for a solution. Throughout the Application Engineering department, our level of experience here combined with the customer’s knowledge of their setup, sometimes results in a solution that is not straightforward. Sometimes, we have to think outside of the box.

What kind of application may we have encountered where the obvious solution wasn’t the one that worked? One of the best applications that came to mind for me is when a customer was attempting to lift/pick up a very porous piece of filter media like the pre-filter from a Heavy Duty HEPA Vac. This material is extremely lightweight and porous. When hearing from a customer, I want to pick this material up, my mind quickly goes to the E-Vac Vacuum generators which are used to generate vacuum to operate suction cups.

In-Line E Vac picking up a block of cut extrusion.

With this material however, the vacuum flow needed is quite extensive and there is another product which is going to be a more efficient use of compressed air. That product, the Super Air Amplifier. As you can see in the photo below, a 2″ Super Air Amplifier easily lifts the porous material and because the suction side is a nominal hose size a hose can easily be attached if needed. The image shows a single amplifier lifting a larger sheet from a bench, these could be organized in an array like suction cups to pick materials up.

Model 120022 – 2″ Super Air Amplifier picking up a porous pre-filter material.

The moral of the story is to keep an open mind for solutions, while one path will always work other paths may become a more efficient manner. These solutions don’t always fit inside a box nice and neat. The Super Air Amplifier fit this because the amount of air entrained is tremendous and can easily be utilized to pull low vacuum force/high flow applications. This is very similar to fume evacuation which would be a “normal” application for the Super Air Amplifier.

If you want to discuss any point of use compressed air application with us, contact an Application Engineer and let us help you determine the solution your job needs.

Brian Farno
Application Engineer