Compress Air with No Moving Parts! - Trompe

this is the ragged chute hydropower plant on the Montreal River in Eastern Ontario Canada it doesn't look like much from an aerial photo but that's because of the most interesting parts of this facility are underground - massive vertical shafts and a large tunnel connecting the two before it was converted to generate electricity ragged chute was one of the world's only water powered compressed air plans starting around 1910 this plant sold compressed air to be used in the silver mines around cobalt Ontario the way this ingenious facility harnessed the power of water to generate compressed air with no moving parts is fascinating and its use is seeing a small revival in modern days am grady and this is practical engineering on today's episode we're talking about the trunk [Music] this video sponsored by Skillshare click the link in the description to get two free months of premium membership and explore your creativity more on that later the breast air is an excellent way to store and transport energy it's not quite as convenient as electricity for homes and businesses which is why you don't see airlines strung on poles throughout our cities but in certain situations it makes a lot of sense this is particularly true in mines where a variety of tools and equipment need a consistent and safe source of power but it's not just pneumatic tools pretty much every step of the mining process including exploration blasting ventilation smelting and refining makes use of compressed air as a source of power it's reliable simple easy to transport and often safer than other options because it doesn't have the risk of sparks or explosions that come with electricity or diesel we normally get compressed air from a compressor a device that does exactly what you'd expect uses a mechanism to take outside air and squish it into a tank but air compressors had a major disadvantage to the mining professional of the early 20th century they didn't exist or at least not ones that were commercially available also a compressor is just an energy converter it takes one type of energy usually rotational kinetic energy from a diesel or electric motor and converts it into potential energy stored in pressurized air you still need a source of power so to be able to operate a mine using compressed air back in the day would have required both maintaining a separate source of power and a complicated and custom piece of machinery just to keep the tools and equipment running you can imagine how valuable it would be to take advantage of a natural source of power following water and avoid the need for complicated machinery in moving parts that's exactly what a trompe provided and I've built a miniature version of one so I can show you how it works and of course it's made of clear pipe so we can see exactly what's going on inside the first step is water supply just like hydroelectric facilities the amount of hydraulic energy you can convert to compressed air is based on both the height and flow rate available in my case I'm using a garden hose but most Trump's built for mines or forges took advantage of small streams or rivers as the water enters the first vertical shaft it passes by a series of air inlets because of the waters velocity as it travels down the shaft the pressure at these inlets goes below atmospheric so the Trump sucks air from outside into this vertical shaft to join the water the turbulence and surface tension of the flowing water entrains these bubbles of air and carries them to the bottom of the shaft this type of interaction between flowing water and air is fairly complicated to characterized and there are lots of situations in engineering where air water interaction can cause major problems like in spillways control gates and pipelines but in a trough this is absolutely essential once the air water mixture reaches the bottom of the shaft it enters a horizontal chamber the purpose of this chamber is to separate the air and water the turbulence and velocity are reduced allowing the entrained bubbles to rise upwards this air gets trapped in the collection system while the water continues out the other side of the chamber and upwards into the second vertical shaft the purpose of this shaft is to give the water a way out while leaving the air behind the height of the shaft also determines the pressure of the trapped air I have a video on this topic if you want more detail but the summary is that the pressure in a body of fluid doesn't depend on the volume just the depth so a simple riser like my second pipe here is enough to hold pressure on the air in the collection system compressing it just like a mechanical compressor would once enough air is collected in the system I can open the valve to use it I should say this is a scale demonstration so it doesn't do anything of significant value unless you have a really tiny nail gun or air drill it's pretty satisfying to see it work I could watch this all day [Music] [Music] one of the benefits of a Trump over a more traditional air compressor is related to temperature in technical terms a compressor uses an adiabatic process where a trunk compresses air isothermally but there's no need to get caught up in the vocabulary if you're familiar with the behavior of gases you know that all other things staying the same if you compress a gas that gets hot and the hotter the air the more moisture it can hold if you're familiar with air tools or just corrosion in general you know that moisture is one of the tools worst enemies but in a trump the heat of compression gets absorbed by the water so you end up with a much cooler and drier source of compressed air which by the way is the definition of air conditioning something I paid dearly for here in San Antonio and I'm sure those miners in Canada appreciated as well I'm definitely not going to be powering any of my shop tools with my little demonstration here and it wouldn't be a very efficient way to do it even if I could if you've got grid power available it makes sense to use a compressor designed to take advantage of that but sometimes you don't a trompe can be useful in off-grid aquaponics and hydroponics systems that need aeration of the water and in fact the design in my demonstration here came from the late Bruce Leavitt a mining engineer who pioneered the use of small Trump's for aeration and treatment of mining water in remote locations without access to electricity how love to see examples of ancient technologies finding new use in our modern world especially in an age where renewable sources of energy are at the top of our minds the trauma is a really cool way to harvest the power of water for a beneficial use if you've been following my channel for any length of time I hope you've seen the quality of these videos improve I try to read every single comment that gets posted on my videos and I've been surprised to receive a lot of helpful suggestions from fans of the channel genuinely trying to help me get better at this little hobby of mine like you should use a fill light in addition to a key light or you need to fix your plosives or you should add some ease to your animations if you don't know what any of that stuff means neither did I until I started using Skillshare my favorite online learning community trying to learn a new creative skill online often as you spending more time curating which resources are useful instead of actually learning Skillshare lets you skip through that hassle and get straight into moving your creative journey forward like this class by filmmaker Matty Brown about using inexpensive tricks to make a low-budget production look great I have a tendency to get caught up any technical details so I really like his freeform style that doesn't worry too much about gear and encourages experimentation I'm an engineer in the truest and most stereotypical sense so being able to learn creative skills from people like Matty has been really empowering to me if you want to make 2020 a year where you explore a new skill or improve on an existing one click the link in the description to get 2 free months of premium membership from Skillshare thank you for watching and let me know what you think [Music] you

Channel: Practical Engineering

Views: 1,390,504

Rating: 4.9584317 out of 5

Keywords: trompe, air compressor, aeration, compressed air, kinetic energy, hydropower, hydrology, gravitational potential, fluid, air pressure, Practical Engineering, Civil Engineering, Engineer, Grady

Id: uvf0lD5xzH0

Length: 8min 49sec (529 seconds)

Published: Tue Jan 14 2020

Reddit Comments

[u/Duzdroads]

Water powered air compressor used before electric powered compressors.

[u/ThePopeAh]

Very cool - learned something new from Grady, again

[u/GentViking]

I thought it was a French Donald

[u/dcviper]

I kinda wanted to learn more about the trompe in Cobalt, ON being converted to electric generation.

[u/danhezee]

What are the limitations of a trompe? Why aren't they being used to generate electricity along every river in the world?

[u/reindeerflot1lla]

So for off-grid air compression, would it make more sense to build a closed-loop trompe and take advantage of the higher efficiency of pumps, or increase the amount of solar panels or windmills & run compressors.

[u/ImaR0bot]

The coolest application of this effect I’ve seen is in the pulser pump. In this arrangement pulser pump the energy harvested from the falling water is used to move a small portion of the total flow to a higher elevation than it started. I see huge potential for this in irrigation applications but have heard little about it actually being implemented.

[u/fluffykayak]

I still don't understand how the water gets sucked down. Is it because the hose acts as a seal and the water flowing down acts as volume increasing which then sucks the air in?

[u/noahlk01]

Maybe just watch the video?