Tag: industrial air movers

Adjustable Air Amplifiers: Product Overview

Published on by John BallLeave a comment
Adjustable Air Amplifier

EXAIR manufactures two types of Air Amplifiers: Super Air Amplifier™ and Adjustable Air Amplifier™.  The Air Amplifiers can be used to cool, dry, clean, ventilate, exhaust and many other uses.  In this blog, I will focus on the features and benefits of the Adjustable Air Amplifiers.

The main difference between the Super Air Amplifier and the Adjustable Air Amplifier is the fact the Super Air Amplifier has a shim inside of it that sets the gap for the air flow.  Force and flow for the Adjustable Air Amplifier is changed by turning the exhaust plug with a pin wrench.  This will open or close the gap inside, changing the amount of vacuum and air flow.  When the desired performance has been found, we have a knurled lock ring to hold the flow at the desired level. This is great for changing environments where needs are regulated to different conditions.

The Adjustable Air Amplifiers come in either 303 Stainless Steel or Aluminum and are sized from ¾” to 4”.  We offer them in a kit which will add a filter separator and a pressure regulator to the mix.  The filter will clean the compressed air, and the regulator will control the amount of pressure to enable you to “dial it in”, so to say.  We also have a deluxe kit which will add another item, Electronic Flow Control, or EFC.  This unit has a photo-electric eye to control a timing circuit to turn on and off the Adjustable Air Amplifier.  This helps to save on compressed air usage. 

The maximum temperature rating for the Aluminum Adjustable Air Amplifier is 275oF (135oC) while the stainless-steel version is rated up to a maximum of 400oF (204oC).  The stainless steel version is also used for chemical resistance and food applications. 

They do not have any moving parts, so they will last a long time and require no maintenance. Since they do not employ a motor, they create a laminar airstream which makes them effective and quiet.  They use a Coanda profile to generate a low pressure on one side to entrain a large volume of ambient air along with the primary, compressed air flow.  The Air Amplifiers amplify the exhaust air up to 24:1, making them very efficient for the compressed air used to create the output flow.  They are designed to have hoses attached to the discharge or suction side if you wish to move the air to or from another location. 

EXAIR has many uses worldwide where our Air Amplifiers are being used.  If you have any questions or would like to discuss your application, you can contact the Application Engineers at EXAIR.  We would be happy to help. 

John Ball                                                                                     

Application Engineer

Email: johnball@exair.com

Twitter: @EXAIR_jb

Buy 1, Get 40 Free

Published on by Al WooffittLeave a comment

Buy one, get one free is a phrase many of us are familiar with. Most of the time it is a good thing; we all like free stuff. What would you say to buy one, get 30 free? Or even 40 free? That’s not far off how our Air Knives perform. They entrain large volumes of ambient air, so for every 1 SCFM of compressed air you are paying for, you are getting 30–40 SCFM of additional free ambient entrained air.

So how are our Air Knives able to do this? We explain this phenomenon in more detail in this blog here, but in summary, a Super Air Knife takes advantage of the Venturi Effect. Named after Giovanni Venturi, who found out that when you increase the speed of a fluid through an orifice, the surrounding fluid will move along with it. This creates a region of low pressure, and the faster the speed, the lower the pressure. With low pressure, the air around rushes in to fill that gap and join the airstream. The quantity of ambient air that gets ‘pulled’ into the airstream is entrained air, or free air.

The engineered surface of the Super Air Knife is designed to minimize as much loss in air speed as possible, which maximizes the amount of free air that is being entrained. The ratio between free air and compressed air used is called the amplification ratio. Super Air Knives have an amplification ratio of 40:1, with our Standard Air Knives having an amplification ratio of 30:1. For comparison, a pipe with holes drilled will have an amplification ratio of between 2:1 and 5:1. As you can see, with a Super Air Knife you are getting a much better deal on your compressed air usage.

This additional free air adds more mass, which allows the Super Air Knife to do more work. You will get a harder hitting force than a comparable product while using less compressed air. This makes Super Air Knives especially good for cooling and drying applications, where moving large volumes of air is ideal.

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 air from the surrounding environment.

It’s not just our Air Knives that take advantage of the Venturi effect to produce large amplification ratios. Many of our products are designed with efficiency in mind, including our Air Amplifiers, Air Wipes, and Air Nozzles and Jets, to name a few. If you would like to discuss how an EXAIR engineered compressed air product can amplify your process, then give us a call!

Al Wooffitt
Application Engineer

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Vortex Tubes For Spot Cooling Processes

Published on by Al WooffittLeave a comment

EXAIR’s Vortex Tubes are a great product for many cooling applications. When supplied with a clean and moisture-free source of compressed air, they will generate two streams of airflow, one hot and one cold. They are a low-cost and reliable solution, capable of producing temperatures ranging from -50°F to +260°F. We have flow rates from 2 SCFM to 150 SCFM, producing refrigeration over 10,000btu/hr.

We also have several other product lines that are great for cooling, like our Air Knives or Air Amplifiers. So, why would you choose a Vortex Tube? Our Air Knives and Amplifiers cool primarily by moving large volumes of ambient air. If you have a 400°F part that needs cooling to under 100°F, then hitting it with large amounts of 70°F ambient air is going to rapidly bring the temperature down. This does mean that there is a limit to how low of a temperature you can achieve with these products; our Air Knives and Amplifiers won’t be able to cool below ambient temperatures. Our Vortex Tubes, on the other hand, with temperatures as low as -50°F, can provide much more powerful cooling and targeted cooling.

Now you have determined that a Vortex Tube is right for you, you’ll need to decide between our two different series: 32XX and 34XX. The difference between the two model types comes down to the Cold Fraction, which is determined by where the Control Valve is positioned. When you open the Control Valve (by turning it counterclockwise, as shown by the blue arrow in the photo to the right), it decreases the Cold Fraction, which leads to a reduced flow and a significant drop in temperature in the cold air discharge. Conversely, closing the Control Valve (by turning it clockwise, indicated by the red arrow) boosts the cold air flow, but causes a smaller temperature drop. This ability to adjust is crucial for the Vortex Tube’s flexibility.

 You can set the Cold Fraction as low as 20%, which means that a small portion (20% to be precise) of the supply air is sent to the cold end, resulting in a significant temperature drop. On the flip side, you can crank it up to 80%, meaning that most of the supply air heads to the cold end, but the temperature drop won’t be as drastic. Our 34XX Series Vortex Tubes are designed for cold fractions between 20–50 %, while the 32XX Series caters to 50–80 % Cold Fractions.

So how do you select the right model for you? To determine this, you need to know what temperature and flow will best serve your application. For most situations, the ~20°F produced by an 80% cold fraction is sufficiently cold. At this cold fraction, you will get the most flow (80% of the inlet supplied). Applications like welding or brazing benefit from higher flows. When your starting temperature is hundreds of degrees Fahrenheit, there is little difference in blowing -20°F air vs +20°F. What you need is more volume to strip away the heat as quickly as possible. In this instance, a 32XX series is the way to go.

If you need lower flow, or to achieve freezing temperatures, then the 34XX series would be the best choice. A chocolate maker took advantage of the lower flow rates offered by this type of Vortex Tube as they didn’t want the airflow to disturb the surface of the chocolate as it cooled, affecting the finish. The greater temperature drop allowed for rapid cooling without reducing quality.

Vortex Tubes can produce higher levels of noise than our Knives and Amplifiers, so we would always recommend using hot and cold mufflers with them. This will ensure they stay within OSHA sound standards. And just like with all EXAIR products, it’s a good idea to use a pressure regulator with a gauge right where you’re using it. This is especially crucial for Vortex Tubes if you want to get an accurate temperature.

Whatever your cooling application, our Vortex Tubes will likely be able to help. If you would like to discuss it, please give us a call!

Al Wooffitt
Application Engineer

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Super Air Amplifier vs Fan

Published on by Al WooffittLeave a comment

One of the more common applications we work with is cooling. In most instances, the goal is to cool the part as quickly as possible. In order to cool faster, you would think that blowing the coldest air possible would be the best option. Our Vortex Tubes can produce air as cold as -50°F! However, in many instances, more effective cooling will be achieved through larger volumes of air. As long as the ambient air temperature is lower than the target temperature, larger volumes of ambient air will outperform a small volume.

Our Super Air Amplifier is a great option for producing large volumes of laminar (non-turbulent) airflow for minimal compressed air consumption. Using a Coanda profile along with a patented shim, compressed air exits the Amplifier in a manner that generates a low pressure zone, which helps pull in the surrounding ambient air. This creates an amplification ratio of up to 25 times! Due to the laminar output flow having the same speed and direction, it is very effective at removing heat from a target. It also helps keep noise levels down.

The most common, non-compressed air alternative to our Amplifiers is an electric fan. Fans utilize motors and blades to direct air towards their target. When air comes in from behind the fan, the blades push the air forward to the target. This action generates turbulent air flow, as well as a lot of noise. Due to the use of motors, there are parts that can wear out over time, leading to additional maintenance costs over the lifetime of the fan.

Ultimately, when it comes to cooling, what we care about most is how quickly a given solution will get the job done. Is a Super Air Amplifier going to cool faster than a fan? In the video below we put both options to the test. As you will see, the Super Air Amplifier is significantly faster:

If you have a cooling application that you would like to discuss, give us a call!

Al Wooffitt
Application Engineer

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