## People of Interest: Daniel Bernoulli

Whenever there is a discussion about fluid dynamics, Bernoulli’s equation generally comes up. This equation is unique as it relates flow energy with kinetic energy and potential energy. The formula was mainly linked to non-compressible fluids, but under certain conditions, it can be significant for gas flows as well. My colleague, Tyler Daniel, wrote a blog about the life of Daniel Bernoulli (you can read it HERE). I would like to discuss how he developed the Bernoulli’s equation and how EXAIR uses it to maximize efficiency within your compressed air system.

In 1723, at the age of 23, Daniel moved to Venice, Italy to learn medicine. But, in his heart, he was devoted to mathematics. He started to do some experiments with fluid mechanics where he would measure water flow out of a tank. In his trials, he noticed that when the height of the water in the tank was higher, the water would flow out faster. This relationship between pressure as compared to flow and velocity came to be known as Bernoulli’s principle. “In fluid dynamics, Bernoulli’s principle states that an increase in the speed of fluid occurs simultaneously with a decrease in static pressure or a decrease in the fluids potential energy”1. Thus, the beginning of Bernoulli’s equation.

Bernoulli realized that the sum of kinetic energy, potential energy, and flow energy is a constant during steady flow. He wrote the equation like this:

Equation 1:

Not to get too technical, but you can see the relationship between the velocity squared and the pressure from the equation above. Being that this relationship is a constant along the streamline; when the velocity increases; the pressure has to come down. An example of this is an airplane wing. When the air velocity increases over the top of the wing, the pressure becomes less. Thus, lift is created and the airplane flies.

With equations, there may be limitations. For Bernoulli’s equation, we have to keep in mind that it was initially developed for liquids. And in fluid dynamics, gas like air is also considered to be a fluid. So, if compressed air is within these guidelines, we can relate to the Bernoulli’s principle.

1. Steady Flow: Since the values are measured along a streamline, we have to make sure that the flow is steady. Reynold’s number is a value to decide laminar and turbulent flow. Laminar flows give smooth velocity lines to make measurements.
2. Negligible viscous effects: As fluid moves through tubes and pipes, the walls will have friction or a resistance to flow. The surface finish has to be smooth enough; so that, the viscous effects is very small.
3. No Shafts or blades: Things like fan blades, pumps, and turbines will add energy to the fluid. This will cause turbulent flows and disruptions along the velocity streamline. In order to measure energy points for Bernoulli’s equation, it has to be distant from the machine.
4. Compressible Flows: With non-compressible fluids, the density is constant. With compressed air, the density changes with pressure and temperature. But, as long as the velocity is below Mach 0.3, the density difference is relatively low and can be used.
5. Heat Transfer: The ideal gas law shows that temperature will affect the gas density. Since the temperature is measured in absolute conditions, a significant temperature change in heat or cold will be needed to affect the density.
6. Flow along a streamline: Things like rotational flows or vortices as seen inside Vortex Tubes create an issue in finding an area of measurement within a particle stream of fluid.

Since we know the criteria to apply Bernoulli’s equation with compressed air, let’s look at an EXAIR Super Air Knife. Blowing compressed air to cool, clean, and dry, EXAIR can do it very efficiently as we use the Bernoulli’s principle to entrain the surrounding air. Following the guidelines above, the Super Air Knife has laminar flow, no viscous effects, no blades or shafts, velocities below Mach 0.3, and linear flow streams. Remember from the equation above, as the velocity increases, the pressure has to decrease. Since high-velocity air exits the opening of a Super Air Knife, a low-pressure area will be created at the exit. We engineer the Super Air Knife to maximize this phenomenon to give an amplification ratio of 40:1. So, for every 1 part of compressed air, the Super Air Knife will bring into the air streamline 40 parts of ambient “free” air. This makes the Super Air Knife one of the most efficient blowing devices on the market. What does that mean for you? It will save you much money by using less compressed air in your pneumatic application.

We use this same principle for other products like the Air Amplifiers, Air Nozzles, and Gen4 Static Eliminators. Daniel Bernoulli was able to find a relationship between velocities and pressures, and EXAIR was able to utilize this to create efficient, safe, and effective compressed air products. To find out how you can use this advantage to save compressed air in your processes, you can contact an Application Engineer at EXAIR. We will be happy to help you.

John Ball
Application Engineer
Email: johnball@exair.com

## Meet New EXAIR Application Engineer, Dann Woellert

I’m one of the newest to join the team of ‘airheads’ here at EXAIR. By airheads I mean application engineers. These guys have forgotten more about compressed air applications than most will ever know. I’m humbled to join this team of compressed air vigilantes.

The cool thing about the group is that everyone comes from a different industry, and brings a unique perspective to the game. My windy road here has come through a couple of industries – Printing, Restaurant Equipment, Automotive, and Label & Packaging – all of which use the intelligent compressed air devices EXAIR manufactures. Most recently I was a product manager in the roll-fed label industry, which uses Line Vacs to pull waste from slitter and rewinders for collection. We also used Super Ion Air Knives to reduce static when marrying silicon coated plastic liner to the label face stock. It’s important to have a consistent pull on the waste so that clean slits can be made in the product. That’s important downstream to the printer and label converters, and even further to the end user who places the finished label on a bourbon bottle.

I’ve also seen the value of Cabinet Coolers a in hot manufacturing environment, where temperatures over 110 degrees could shut down a panel faster than you can say lost profits. One of EXAIR’s latest products, the Soft Grip Super Air Scraper would also be invaluable to operators who clean out the attritors, which mix dried pigment into viscous varnish.

I’ve been impressed with the positive team attitude here at EXAIR that clearly flows into product design and our go-to-market. I’m also amazed at the creative wizardry of our marketing team to create product images for our promotional content. If a picture is worth a thousand words, EXAIR’s are worth a factor more. Then there’s the videos presented in this blog by the team of airheads. While none of us has a degree in filmmaking from NYU, the App Engineering department creates incredible videos to help customers understand the intricacy and design of EXAIR products.

With a full team of application engineers ready to offer real time support through online or phone chat, EXAIR takes a B2B experience and makes it seem like a true B2C personal experience.

Out of work I’m a food and history geek. I enjoy travelling the region looking for the weirdest and most unique dishes. I am told there’s a Sharonville Superfecta – four signature dishes from local diners – that I need to try. There’s the Bronx Bomber pizza, a gyro from Athenian Greek Diner, a Sammy Burger, and a float from the Root Beer Stand. I’ve recently taken on a side hobby of fermenting my own sauerkraut and hope to have a supply ready soon.

I look forward to embracing the flow and helping you solve your applications with EXAIR’s robust family of intelligent compressed air products.

Dann Woellert
Application Engineer

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## People of Interest: Daniel Bernoulli (2/8/1700-3/17/1782)

Daniel Bernoulli was born in the Netherlands in February of 1700. Mathematics was in his bloodline as the son of renowned Swiss mathematician, Johann Bernoulli. He and Johann’s brother, Jakob, both took jobs as professors at a university in Basel, Switzerland. Fittingly, Johann taught Daniel mathematics at a very young age. Daniel Bernoulli spent some time studying a variety of topics including philosophy, logic, and medicine. Daniel obtained his Bachelor’s Degree at the age of just 15, earning his Master’s Degree just one year later.

Daniel was well-known and was highly regarded among scholars throughout Europe. After spending some time teaching Botany, he switched to physiology topics in 1743. This continued for several years when in 1750 he was appointed to the chair of physics where he taught at Basel for 26 years. During this time, he also received a total of 10 grand prizes from the Paris Academy of Sciences for work he completed in astronomy, a variety of nautical topics, and magnetism.

Daniel is most commonly known for his work in developing what is now called Bernoulli’s Principle, which discusses the relationship between fluid speed and pressure. An increase in the speed of a fluid will occur simultaneously with a decrease in the fluid’s pressure or potential energy.

The air entrainment properties of some of EXAIR’s Intelligent Compressed Air Products can be explained through Bernoulli’s Principle. As high-velocity air exits the nozzle of a Super Air Knife, for example, a low-pressure area is created that speeds up and draws in ambient air at an astonishing rate of 40:1. The same also occurs with the Super Air AmplifiersAdjustable Air Amplifiers, and Air Nozzles. To find out how you can utilize this advantage to save compressed air in your processes, give us a call. An Application Engineer will be happy to help assist you in determining the most suitable products for your application.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@exair.com

## Compressed Air Uses In Industry

From pneumatic hand tools like impact wrenches or nail guns to larger scale industrial applications like stamping presses, the use of compressed air can be found in almost any industry. In fact, it is often referred to as a “fourth utility” next to water, gas and electric.

Take for example in construction, workers will use a pneumatic riveter to join steel framing because of the power generated by the tool over an electrically powered device, not to mention it provides for a safer operation by removing an electrical hazard. Many companies use compressed air operated diaphragm pumps or air motor driven pumps to move expensive or viscous liquid from one location to another. These types of pumps are self priming drawing the liquid in and provide positive displacement meaning they fill and empty the liquid chamber with the same amount of liquid through a common inlet and outlet.

Amusement parks have used compressed air in some capacity in the operation of thrill rides like roller coasters or to enhance the effect of certain attractions. Compressed air can be found in hospitals where it is used for specialized breathing treatments or to power surgical instruments in an operating room. Educational facilities use compressed air for laboratory testing. You can even find compressed air in the tires on your car. Basically, when you think about it, compressed air is being used just about anywhere.

Here at EXAIR, we manufacture Intelligent Compressed Air Products to help improve the efficiency in a wide variety of industrial operations. Whether you are looking to coat a surface with an atomized mist of liquid, conserve compressed air use and energy, cool an electrical enclosure, convey parts or dry material from one location to another or clean a conveyor belt or web, chances are we have a product that will fit your specific need.

To discuss your particular application or for help selecting the best product, contact an application engineer at 800-903-9247 for assistance.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Compressed Air Valves image courtesy of Shane Gorski via creative commons license.

## EXAIR Application Details Guide

The EXAIR website is valuable resource for reviewing and getting information about the many Intelligent Compressed Air® Products that we manufacture and sell.  It is a good place to learn more about the products, how they work, calculate air savings, see the many styles and materials of construction and much, much more.

If you have a specific application and would like us to review the process parameters and get our recommendation as to the best way to solve the issue, you can utilize the Application Assistance Worksheet located on the Left Menu Bar on many of the Product Pages.

Clicking on the Application Assistance Worksheet will provide you with a couple of ways to access the form.  Choosing one of the options will present you with the form below.

This form has sections regarding Process Description, Part Specifications, Product Movement, and Other for general information.  By filling out this form with as much detail possible, and then online submitting or emailing to applications@exair.com, one of our Application Engineers will review and be in contact with you to further discuss in preparation for presenting a solution for you.

Or – to discuss your processes and how an EXAIR Intelligent Compressed Air® Product can provide a beneficial service, feel free to contact EXAIR and myself or one of our other Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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

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

## 20 Year Old Cabinet Cooling System Still Working Today

Very soon after I received a text message with the below photo attached. Sure enough, my uncle had come across an EXAIR Cabinet Cooler System installed in his facility.  Based on the photo, I identified it as a NEMA 12 model, with a cooling capacity of 275 or 550 BTU/hr. When I did an order history search, I confirmed it was a model 4208 (550 BTU/hr) and found it had shipped in August of 1995, and that my uncle’s name was listed as the order contact, since he placed the order.

Small World!

Speaking of small worlds, the model 4208 and it’s little brother model 4204, are perfect for small cabinet enclosures that have a minor amounts of internal heat generation, such as a power supply, or moderate outside heat transfer.  Capable of producing 550 BTU/hr and 275 BTU/hr of cooling while using just 8 and 4 SCFM of 100 PSIG compressed air, the EXAIR Cabinet Cooler Systems offer a great way to keep cabinets cool and worry free, as evidenced by over 20 years of operation.  Just provide clean air (a simple 5 micron water/dirt filter is recommended) and it will operate worry free for a long time.

EXAIR manufactures Cabinet Cooler Systems from 275 to 5600 BTU/hr, for NEMA 12, NEMA 4 and NEMA 4X enclosures. They are available in Continuous Operation, (2) Types of Thermostat Control, special designs for High Temperature environments, and a Non- Hazardous Purge. Materials of construction include aluminum, stainless steel, and type 316 stainless steel.

To discuss your application and how an EXAIR Cabinet Cooler System would help out, feel free to contact EXAIR and one of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer

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