Tag: Super Air Amplifier

People of Interest: Henri Coanda 1886 – 1972

Published on by John BallLeave a comment
In each of these EXAIR engineered compressed air products, the primary air stream following the curved surface causes entrainment. And efficiency.

Being in the compressed air industry for over 35 years, you come across many interesting people from the past that have created laws that we are still using today.  Henri Coanda is one of those people. 

Henri Coanda was a prominent Romanian inventor and aerodynamics pioneer.   In 1910, Henri and his Italian counterpart, Gianni Caproni, began a partnership to construct an experimental aircraft which was later called the Coanda-1910. The Coanda-1910 was unlike any other aircraft of its time as it had no propeller; instead, it sported an oddly shaped front end with built-in rotary blades arranged in a swirl pattern. These blades were driven by an internal turbine screw that would suck air in through the turbine while exhausting the gases out of the rear, propelling the plane forward. This initial jet engine was quite impressive for the time, but sadly nobody believed it would ever fly, and it is believed that it never did achieve flight. Coanda is not credited with the invention of the jet engine, but his technology spurred the future of aviation into the future.

Henri spent his time developing the turbo-propeller drive system of his 1910 Biplane during World War 2.  After it ended, Henri began furthering his research on the Coanda Effect which would become the basis for several investigations into entrained and augmented flow of fluids.  It states that a fluid adheres to and follows a contour which creates low pressure.  Later, in 1969, Henri would spend the last of his days in Romania serving as Director of the Institute for Scientific and Technical Creation.  Henri died on November 25, 1972, in his hometown of Bucharest.

Henri Coanda passed away on November 25, 1972, in his hometown of Bucharest.  Here at EXAIR, we have used the Coanda Effect to apply it to several of our products.  This helps to amplify total airflow by using less compressed air.  Thus, saving you money.  The most notable products are our Air Amplifiers, Air Wipes, Standard Air Knives, and Full-Flow Air Knives, which are some of the most efficient products of their kind.  If you would like to speak more about how EXAIR can benefit your pneumatic system, one of our Application Engineers can help you determine the best solution.

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

Standard Temperature and Pressure: What is STP?

Published on by John BallLeave a comment

When it comes to volumetric flow rates, you probably noticed the prefix of an “S” for SCFM and SLPM, or an “N” for NM3/hr.  The “S” prefix is for Standard conditions, and the “N” prefix is for Normal conditions.  For practical reasons, they are the same thing.  What does this mean? 

Let’s look at the Ideal Gas Law in Equation 1:

Equation 1:

PV = nRT 

P – Pressure

V – Volume

n – No. of moles

R – Ideal Gas constant

T – temperature

Since air is compressible, it will react in different ways.  If we keep the volume the same and lower the temperature, the gas pressure will go down.  If we keep the temperature the same and decrease the volume, the gas pressure will go up.  If we go to a higher elevation, the number of moles is reduced, which will lower the gas pressure.  With the different degrees of changes, it is difficult to compare.  So, organizations decided to place a standard on these conditions to help compare results.  The definition is referred to as STP, or Standard Temperature and Pressure. 

In most cases, the Standard Temperature and Pressure is set at 20oC and 1 atm (1.013 bar).  If we transition all pneumatic units to this condition, we can then compare the results for each product.  We can determine which units actually use less compressed air or have higher forces.  Or if we decide to use a different STP, we can do that as well as long as we use the same temperature and pressure. 

I like to think of it like an air-filled balloon floating on top of the water.  This would be the “Standard” or “Normal” condition.  As you take the balloon into deeper water, more pressure is applied to the balloon, and the volume will decrease.  This is because air is compressible.  The balloon still has the same amount of air by weight (as the volume decreases, the density increases).  If you return to the surface, the balloon will expand back to the original size.  When doing comparisons, we need to be in the same condition, or for the balloon example, it will look like the balloon will need less air at lower depths than at the surface.   

The reason for this explanation is that some competitors like to use lower pressures to rate their products.  As an example, Competitor A rates their nozzles at 5 bar (72.5 psig).  EXAIR uses 5.5 bar (80 psig) for most of our products.  By comparison, we cannot say if one unit uses more or less compressed air unless we set them at the same conditions.  The best place to compare is at a Standard Temperature and Pressure, or STP.   I go into more detail in my blog about air flows with “CFM, ICFM, ACFM, SCFM: Volumetric Flow Rates Explained”.  EXAIR offers Super Air Knives, Super Air Nozzles, and Super Air Amplifiers to efficiently blow compressed air.  So, when a company states a compressed air flow, verify the pressure and temperature at which they recorded that information.  It will help you to be more in tune with what you are getting (allow for an apples to apples comparison). If you need any help in doing comparisons, an Application Engineer at EXAIR will be happy to assist you. 

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

Photo:  balloon helium air flying bright by stux.  Pixabay license

What is Sound, and How Can You Reduce It?

Published on by John BallLeave a comment

Many manufacturing plants have a strong focus on safety for their workers.  One major safety concern that is commonly overlooked is noise.   Occupational Safety and Health Administration, or OSHA, has a directive that defines the noise exposure over a time-weighted average; 29CFR 1910.95(a).   For an eight-hour day, the maximum noise level is 90 dBA.  The Center for Disease Control, CDC, reports that “approximately 18% of all manufacturing workers have hearing difficulty”1.

What is sound?  In the simplest of terms, a decibel is one-tenth of a bel.  Historically, bel was a unit created to honor Alexander Graham Bell, who invented the telephone.  Like the frequency waves that travel through telephone wires, pressure waves travel through the air as sound.  This sound pressure is what our ears can detect as loudness.  EXAIR offers a Digital Sound Level Meter, model 9104, that is calibrated and can measure sound in decibels.  It is very important to know the sound level, as it can permanently damage your ears.

Here is a test for you.  If you go and stand in your plant, you can probably hear loud noises coming from your compressed air system.  EXAIR has an engineered product to solve most of them.  On the Hierarchy of Controls for NIOSH, Personal Protection Equipment, PPE, is the least effective.  A better control would be to isolate your operators from the hazard with an engineered product.  EXAIR can offer that solution for many of your blow-offs and pneumatic discharges to reduce noise levels.  This would include; but not be limited to; Super Air Nozzles, Safety Air Guns, Super Air Knives, and Super Air Amplifiers. 

Let’s look at a ¼” open copper tube.  It can create a sound level of over 100 dBA.  They are commonly used because they are readily available and inexpensive to make.  But they waste a lot of compressed air, as well as creating a hazard for your operators.  Just by adding a model 1100 Super Air Nozzle to the end of the copper tube, we can reduce the noise level to 74 dBA at 80 PSIG (5.5 bar).  Wow!  Not only will it remove the hazard, but it will reduce the amount of compressed air usage; saving you money.  Here is a quick video to show the importance of the EXAIR Super Air Nozzles.

At EXAIR, we have a statement, “Safety is everyone’s responsibility.”  EXAIR manufactures engineered products with high quality, safety, and efficiency in mind.  To keep your operators safe, EXAIR offers many different types of blow-off products that are designed to decrease noise to a safe level.  So, here’s to Alexander Graham Bell for creating the telephone, which you can use to contact an Application Engineer at EXAIR.  We will be happy to help to reduce your sound levels. 

John Ball
Application Engineer


Email: johnball@exair.com
Twitter: @EXAIR_jb

Note 1: https://www.cdc.gov/niosh/topics/ohl/manufacturing.html

Air Amplifiers – Done Your Way

Published on by bdwagesLeave a comment
Photo by Ryan McGuire Licensed by Pixabay

Air Amplifiers are amazing tools that pack a punch (if the punch is a ton of air flow). Imagine an amplification rate up to 25 times. You supply 29 SCFM and yield 730 SCFM coming out? It’s incredible. These little beauties work by flowing compressed air (80psig) through the inlet to the annular chamber. It is then throttled through a small ring nozzle at a high velocity. This Airstream employs the Coanda profile directing all this air to the outlet. Although you should never blow air at a person, a little bit of air input, would easily produce the results to the right!

Why would you use these? See below for starters:

Although we have many options to choose from, sometimes you may need something outside the box. Maybe it’s a different size? A different Material? A different fitting? Ask us we do have many ways to customize this product. Here are 3 examples of things we have done in the past.

The High Temp Air Amplifier (right) was developed for moving hot air to surface needing uniform heating while in a furnace or oven. This is designed for temps up to 700°F, and is now a standard offering in 1 1/4″.

Another example of a “Special” Air Amplifier is a stainless steel version with a flange mount (left). This was designed for exhausting flue gases from a furnace. If there were a power failure, this Special Air Amplifier will quickly evacuate harmful fumes, prior to affecting the workers.

A third “Special” was made when we were brought an application that required a sticky material to be pulled through the Air Amplifier, and it was unable to stick to the inside of the Amplifier. So we developed an Adjustable Air Amplifier with e PTFE Plug (Right), so the material would not stick.

If you have an application that requires a tool that is not quite in line with what we offer, don’t hesitate to reach out. I can’t promise you that we will be able to make it for you, but I can promise you that we will look at it and give it our best shot.

Thank you for stopping by,

Brian Wages

Application Engineer EXAIR Corporation
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