Characterizing the cyclone

[@MrPinchegabacho]

I work at a company that makes cyclones for chemical and mining industries as well as other uses. Ours typically has a cone section underneath the head as well as a part called a vortex finder installed on the outlet or overflow. That may help with your efficiency without having to upgrade your motor. Hope this helps!

[@RetroBuiltGames]

I truly appreciate your scientific approach and explanation when searching for better performance in your projects. solid work.

[@COLDB33R]

Just what I was going to say. Lots of similar channels are full of information, but backing it up with experimental results makes it far more useful.

[@learnerlearns]

WoW! Again I thank you Matthias! I have been researching cyclones for over a year now at various manufacturers' web-sites, dealers, talking to sale-people. NO ONE has come close to explaining and demonstrating how these things work as well as this series of videos!

[@SteveRamsey]

Mind-blowing. (Haha...joke there somewhere.) Very few people make videos this interesting. Especially for those of us who will probably never actually make a blower. Plus, I like the green paint on all your homemade tools.

[@builtrodewreckedit]

I had not imagined it actually working as well as it does. I bet the shop vac lets as much fine flower dust threw its filter as your collector does. Looks great!

[@MichaelIreland]

+Matthias Wandel you could apply some of the same principles as applies to a centrifugal pump whereby fixed curved-wing shaped vanes are added at an offset angle radiating from the centre of the cyclone. (In a pump, the purpose is essentially to convert fluid velocity to pressure) You'd have to either calculate or experiment to get the ideal length of the vanes, and the ideal number of them. My guess is the centre-facing end of the vane would be right at the throat, perhaps overhanging the opening by a smidge. Then the vane would curve away from the centre and reach maybe halfway to the wall of the separator. The intention here is to retain the top-speed of the cyclone at the outer edge, but slow it down closer to the centre. The net reduction in spinning airmass may be sufficient to attenuate the losses, while maintaining the maximum speed at the outer edge to retain maximum separation.

[@gary3ward]

You are an excellent scientist-engineer-woodworker-instructor. Kudos.

[@TylerJCramer21]

Don't know if anyone has said this yet but you should not use a air compressor to blow the dust off the filter. The air compressor creates even more bigger holes in the filter allowing bigger particles to go through. Love your videos!

[@RoamingAdhocrat]

When you opened the container after sucking up the flour - I was hoping to see a freshly-baked bread roll in there!

[@matthiaswandel]

I might try that. I have also been thinking of trying coffee whitener.

[@matthiaswandel]

I could achieve the same thing by putting an obstruction in the chamber. De-tuning a cylone will always reduce air resistance, but also decrease separation performance.

[@Spitts]

Suspicious "white powder". Now we know where Matthias gets all that energy to make so many things. Haha I'm just kidding I love the videos and the way you can explain things without over complicating them. Hopefully I will be able to get a nice woodshop someday soon and start replicating some of your work. You have a way of making it look so fun even though I'm sure it gets very tedious sometimes

[@4sineweaver2]

I love your methodical approach to everything.

[@matthiaswandel]

I experimented with some catcher vanes in the middle, but in the end, I couldn't tell that they made a difference, and without vanes, it's less likely to jam, and I can reach in there to clear it out if I have to.

[@matthiaswandel]

Any obstruction in the cyclone makes it have less air resistance, but also makes it less effective at separating.

[@matthiaswandel]

Many smaller cyclones would be a bad idea for woodworking - some of the planer shavings can be quite large and would jam the cyclone. But all cyclones are ineffective at catching microparticles, so a filter is unaviodable.

[@matthiaswandel]

I might try making it smaller if I do it again. But it's a tradeoff - separation effectiveness vs pressure drop.

[@rbechard]

You want to drop down that chimney (vortex finder) to around the same depth as your air intake. This reduces short circuiting of your air flow, which would allow fine particulates to escape by not spending much time in your cyclone. The vortex finder also helps form your outer vortex and guide your centre vortex. Not sure how it will work on your cyclone since I'm more familiarly with cyclones with tapered bottoms - but it's worth a shot! Best of luck!

[@woodmasterguy]

Matthias, Try a 2-3" chimney on the top portion of your seperator pointing down towards the bucket. This will stop some of the fines getting to the filter on a single stage unit. Even with our cyclones in our shops, we still have to deal with fines in our filters...

[@matthiaswandel]

Certainly thought about it, but I wanted to keep the unit compacti, which is why i used a thien baffle type cyclone.

[@randacnam7321]

The centripetal force is a force that acts on the particle to keep it moving on a curved path, and it acts towards the instantaneous center of rotation, not outwards. It is also a phantom force that one of the other forces in the system is serving as.

[@matthiaswandel]

Same static pressure, but pressure drops a bit less with flow rate. But efficiency will drop quite a bit.

[@matthiaswandel]

That's been suggested a few times. But what is the reasoning behind that? Personally, I'm thinking that pulling the air in lower would make it worse.

[@matthiaswandel]

There certainly is some leakage against the bucket rim, but it's costing me more volume than pressure.

[@woodmasterguy]

I had Phil Thien help me with my single stage awhile back. The chimney will help to keep the fines from going to the filter. The chimney would be located in the hole located at the top of your seperator. I did try a few different depths. I found on my old 2 hp single stage DC, the chimney worked best being only 1 1/2" above the Thien baffle and 3" above the top of the seperator. I have no way to measure air flow, but I did not see any change in airflow as too the dust picked up @ each tool...

[@matthiaswandel]

I widened the mouth a bit, but it still has a lot of back-pressure. I think the key is to not spin the air quite as hard. Or have a bigger blower!

[@BlackJavaBean]

Have you considered becoming a science teacher? A lot of your videos not only tell the woodworking side of the story, but also the science behind the design. I like how you explain how and why your machines work.

[@matthiaswandel]

Once you guide the air towards the outtake, you also guide the dust.

[@cjorg16]

Nice job capturing onto camera, some difficult to see air movement behaviors. Keep up the good work.

[@Matisse1992]

hi matthias! did you had in mind that you can filter filter more particles by just adding a few smaller cyclones? (thing about the design of a dyson) the air will spin faster and faster, what causes lighter particles to drop in a bucket. you won't need such a large filter at the and if you do. another thing, the los of airflow once it gets to the filter, is not always a bad thing. if the air moves with less speed trough the filter, and particles will have a better chance to stay in there!

[@rorypenstock1763]

The South African nuclear weapons program used a similar system to enrich uranium. The state of the art was to use centrifuges to separate uranium hexafluoride gas by density. The molecules each have only one uranium atom, and those with the heavier isotope end up more concentrated at the outside. But instead they went with a cyclone-like system that does the same thing, but only the gas spins. It seems like a pretty elegant solution if you don't have the high-speed magnetic bearing technology. I bet it costs less to set up, but more to run.

[@matthiaswandel]

Not so simple. The rifling would also force the air down. And the air can't all go down in the bucket, which means it has to come back up, and so now you get a whole lot of turbulence. Rifling may very well do more harm than good.

[@2adamast]

Need a neutral vane? Reading the Bill Pentz site he explains that it is better to avoid a flush entry and to lengthen the tube until the entry stands perpendicular to the walls, to avoid the pressure problem.

[@rbechard]

You're filter will work better as you use it - as you use it the voids get smaller and smaller. The trade off is it takes more energy (larger pressure difference) to use the filter as time passes. You might also want to try to drop down the centre pipe (vortex finder) to try and reduce some short circuiting that may happen with your air flow. I bet you would get a much more effective cyclone that way.

[@Nifty-Stuff]

Mattias, I've watched pretty much all of your videos, but this one blew me away (pun initially not intended) ; ) You really went the extra mile with this video and I really appreciate it, especially as I look into making my own Thiel cyclone dust separator! Keep up the great work!

[@matthiaswandel]

Taking the air from further down is just as likely to make it worse. And I don't have a good way to measure small differences.

[@matthiaswandel]

Nothing new really. That's how pressures like that are measured.

[@RustyCas999]

I have watched many, many videos on seperators, both cyclones & thien-baffle units. My theory - as yet untested - is that neither is necessary. I believe, as others have suggested, that gravity alone is pretty much sufficient if you use a large drum (a 55 gal barrel, for example). Inject the air *below* a baffle and the rapid decrease in air velocity (in the large drum) will allow the dust to simply fall out of the air.

[@raphaelrtw]

+Rusty Cas that actualy wouldn't work as well as you think. A gravity separator would need a lot of space to really work well, and the sawdust is small enough to become airbone with just a breeze. The moving air would simply pick some of the particles that were settled and them again. The cyclone+filter is a very effective way to collect dust.

[@maxdecphoenix]

Fill a bucket with saw dust and then blow on it as hard as you can. The facefull of dust you get for your trouble should remedy you of ridiculous 'theory'.

[@Dave5843-d9m]

Do you need that baffle on the cyclone inlet? Can you make the cyclone air exit at the bottom of the cone? It will do a 180 turn to leave the chamber at the top. You can also use an exhauster paddle Dan on the dirty side with your centrifugal fan on the clean side. Electrostatic plates will catch dust. Charge them with car HT coils or powder coating chargers.

[@deezynar]

The purpose is to get the chunks & dust out, so there'll be a drop in flow to acheive that however it's done, cyclone, filter, baffles, water bath, etc.

[@MostlyInteresting]

Your injector nozzle into the cyclone seems to work a treat. It seems to work so much better than the round elbow most use as the inlet. Have you tried to find a trade off in separation vs restriction?

[@futhaiter366]

the external mic was a good idea ;) well explained and done. thanks for this interesting video.

[@Zigge]

I have been reading and watching your experiments and it is very interesting. I'm very pleased that you take the health issues serious also. May I suggest that you can use some of the colored chalk line powder as tracer on white filter material to test the efficiency? I don't know if it will work, but the red and blue chalk sure makes a mess if you spill it :-)

[@xmozzazx]

I figured there was a reason, I just noticed by observation, that most vacuums have a deflector, doing just that. I also figured you had already explored the idea and had good reasons for not trying it, just wondered why not. :)

[@Rancourt762]

I love these videos. You need your own tv show.

[@matthiaswandel]

Allright. My advice - do as I do,and keep it in a pile.

[@darkokomi]

reducing air resistance = more suction = more dust get out of way, more dust = decrease separation performance and vice versa just need to know what kind of performance you need In any case your dust extracor is very good as is nice job

[@Wolsk]

I had no idea what you were doing, but it was still cool.

[@EyeOnTheTV]

Fascinating video as always. I'm no vacuum expert but I'm wondering if you ever tested the seal on the collection bucket. The earlier video you showed how you mount the bucket and it looked like it's just plastic against wood. Suppose you used a strip of rubber or cloth to shore up any vacuum pressure lost.

[@xmozzazx]

I am thoroughly engaged in this, thank you so much for sharing, I love watching your videos and was extremely happy you did a follow up from the earlier two.

[@BackyardWoodworking]

Very interesting I built one of these the only difference is the intake on mine is longer about 8" I wonder how that would afect the air flow. Mine is going to have 4" intake and exhust ports. I am going to try a blower off a Jen-Air stove ,used for the downdraft vent. I has a squirel cage type of blower. I let you know how it works. Thanks for your video.

[@MacoveiVlad]

An interesting experiment would be to suck in or coat the main cylinder with colored paint/gel, like they do in formula 1 for aero tests on the track. See "formula 1 aeropaint" on google. Another thing to try would be to put different materials on the walls of the cylinder to see what effects do they cause. Plastic, sandpaper, leather and even fur. You would probably need more accuracy on the measurements though.

[@davidpaulbryant]

I believe you should extend the pipe going into the center of the cyclone, to increase separation. Worth a shot?

[@xmozzazx]

If you had something forcing the particles on the exerior wall of the collector downward, small ribs, etc. would that not help the collection of dust? I envision small grooves spiralling down ward or very small 'rifling' in the direction of collection. I suppose it could be something as simple as a wire spiralled on the exterior wall in the direction of flow and downward. You are relying on gravity for the particles to fall, but have a natural upward draft in the middle.

[@christopheleblanc9175]

like the experiments , makes me feel normal,when i redo a project several times to tweak it ,lol

[@murraylowe8677]

Matthius, What if you introduced the intake on the top alongside the discharge without having the intake in the way of the cyclonic action, Also maybe have an internal funnel shape around the out feed tube? Just a question. I love your scientific approach to all the projects you do.

[@meottome]

What would happen if the outer wall of the tilted in on top to change the Speed of the air? Also how did you choice the hight and diametre of the cyclone tower? I have just found your chanel and love it. thanks for al the work in creating these videos.

[@ACHE666SAS]

It sucks that one can only "Like" your vids once... instead of clicking the "Like" button 10 times.... Reeealy good content from obviously a brilliant individual....

[@DamienPollet]

I guess that's the argument for conical cyclones over thin baffle separators. They suck air from lower inside the cone, where the walls are closer (but then, maybe the centrifugal force is even stronger…), so I guess they are more efficient, but take up more space.

[@NMranchhand]

Thanks for taking me into the cave, Aladdin. Much better the lamp than the jewels.

[@Real.Ragnar]

did you notice that with the paddle spinning freely in the cyclone your airflow increased even more?

[@slendy9600]

as someone who plays alot of Fallout i really hope Mathias gets a spot in one of the vaults cause damn we're REALLY gonna need him once the bombs fall :P

[@skidloaders1]

Very interesting, cyclones can be tricky, nicely done, keep'm coming

[@permofit]

you can increase air flow by getting rid of the sharp turns between the cyclone and the blower in HVA/C terms 1 90 elbow is the same as 5 feet of pipe in friction hope that helps plus I have yet to see a bad video keep up the good work

[@plumbersteve]

when you insert the black bracket thing, the pressure increases. If you were to install baffles, to disturb the cyclone and increase the suction, would you be sacrificing centrifugal force?

[@permofit]

o ya and the center pickup tube that the air leaves the cyclone from if you change that from a pipe that points straight down cut it in such a way to scoop the air out of the center of the cyclone otherwise you are making the air change direction 180 relying on pressure instead of the shape of the device helping the air out again just my 2 cents :)

[@michaelmolter6180]

It would have been cool to see more quantitative data on your characterization experiment. Mass the filter before and after a run, what percentage of 500 g of flour does it catch. Mass your collection bucket before and after a run, what percentage of 500 g of flour does it catch.

[@EyeOnTheTV]

Not quite sure what you mean by volume. I would think a bucket seal would force more air in through the hose.

[@jimmyjamjar10101]

This is a cool concept! It's a real man's vacuum. Hope you didn't run that test too much. Don't want you getting baker's lung!

[@curtdaly]

We compromise when we design a device to separate two very dissimilar things. Try this demonstration: stand in front of your dust detector with a hand-full of your calibrated sawdust held at eye level. Drop it. Gravity does a damn fine job of pulling most of what you dropped straight to the floor. AND gravity has little effect on a portion, that just hangs in the air or splashes up from the floor. So maybe it makes sense to treat those two behaviors separately. A gravity separator, with no rotation, does not amplify resistance in a system. It can be schematically modeled as a straight pipe. Visualize a very fat section of pipe, where air speed slows and gravity does it's job. Out the far side goes the airborne stuff that really needs a cyclone. So, if all you need to extract is bits small enough to pass through a window screen, would you design a cyclone optimized differently? Optimized, and therefore more efficient... I don't know where to go from here. Low mass particles need to be moved faster, but for less time? Thanks for sharing.

[@matthiaswandel]

curtdaly Gravity separation doesn't work very well if you have a stream of fast moving air. In fact, the air will pick some of the settled dust back up.

[@larry527az3]

Mattias, I know this is an old video, but don't you think a lot of the air flow loss in your setup is due to the sharp bends in your design? Sharp bends such as your top cover that goes to the filter are the worst for good air flow. Perhaps using some PVC pipe with 45° bends broken up with some straight sections making a 180° total bend to the filter would help with air flow. Not sure if you're still playing around with cyclones but it would be interesting to see if reducing the bends really offer much if any real improvement. As usual, I always enjoy your videos so thanks for making them available.

[@matthiaswandel]

+Larry527az Most of the air resistance comes from the cycoone. Next worse is the hose.

[@DehimVerveen]

Hey Matthias, maybe increasing the diameter of the chamber will increase its efficiency as centrifugal force increases with diameter. Maybe you could even slope the inside of the chamber so as the dust gets down into the chamber the diameter increases and as a result the centrifugal force increases, so the dust gets sucked down even more?

[@guysquarred]

In the video matthias shows that the cyclone is actually pretty good at separating particules (flour here). But he shows also that the cyclone is the biggest source of air resistance due to centrifugal effect. So what you suggesting is counterproductive because with more centrifugal effect the air resistance will increase further and the overall efficiency is likely to decrease !

[@brianwellingtonlewis]

I think a way to probably improve the efficiency of the design overall would be to make the outer inside edge of the cyclone area (where the dust gets thrown to by the centripetal forces) sort of at an angle not quite perpendicular to the axis of air rotation (tapering outwards.) That way, the dust could get pushed down a bit by the centripetal force rather than just by gravity and you could lower the amount of air being compressed/the power needed overall or improve the efficiency somewhere else.

[@nshire]

Nice work mate! When I'm older and have a steady job, I'd love to be just like you :)

[@GRAHAMAUS]

Just a thought but what about reversing the airflow through the cyclone? It will still spin to separate the dust, but then you're working with the pressure gradient instead of against it.

[@NoorquackerInd]

The dust that comes out of the filter is FLIPPING MINUSCULE!!!

[@maxdecphoenix]

Yea, and that's the worst kind. The body has mechanisms for filtering larger particles out prior to reaching the lungs, but is the ultra fine stuff that makes our through and causes onset health issues.

[@Emescher]

What would happen if you reduced the relative volume of the centre like forming the inside bottom like a cone or "half-sphere" (or lense shaped as a actual half.sphere likely won't fit). Would that have any significant effect on the relative air pressure and/or would it disrupt the circulation to much for the dust-separation to be effective?

[@clavierpccam]

really really interesting video ...please Mattias i want to know if i can use the same method to the domestic vacum cleaner at home because the filter price are increasing ...by the way i love your chanel im from morocco

[@imeakdo7]

Pros and Cons of The cyclone Pros Dust collection buckets can be hot swapped by installing a gate Can be made only with The Cone, this way it's easier and cheaper to make and mass manufacture Cons It's taller than a Thien baffle, thus reducing dust capacity it's harder to make on wood

[@TheVisidor]

So is the only way to increase airflow without sacrificing seperation by putting in a stronger louder motor and fan? Throughout the video I was waiting for you to come up with some brilliant way to improve your already nice dust extractor. Would a conical shaped cyclone help?

[@lookwhoneedsahobbie]

"So much magic and it's just an empty box inside" What a great way to end the video. Fantastic work.

[@heckyes]

Hey Matthias, I totally love your channel and this is just a general question for you. I have a bunch of spare wood bits and I'd like to be able to store them all in such a way that makes them easy to access. Currently they are just all in a pile. I'm curious if you have any suggestions on how to organize wood. It's mostly 2x4 and 2x2 general framing lumber from 2 feet to 8ft. There is also a bunch of OSB and regular sheet plywood of varying thicknesses. Any suggestions would be great :D

[@Fentanyl3]

Matthias, is the collection reservoir needed for the cyclone to work? I'm wanting to know if it is possible to leave the slot in the separator open. I generate enough sawdust in one day to fill a pickup bed to the point of squatting. I'd like to have a separator that simply throws the dust on the ground BEFORE it makes it to the suction unit. I'm thinking it will not, but perhaps if the centripetal forces are great enough, it may???

[@TheDct88]

Matthias i have a suggestion not sure how it will work but if you put some sort of rounded pyramid n the centre of the cyclone would that help reduce the air pressure?

[@CHRISANDELLIOT123]

hmm. I might have to give this a try, Ive got an extra motor and some scrap, it should go great with my wooden bandsaw!

[@matthiaswandel]

Purple fountain pen ink, actually

[@aerofart]

Matthias, you should build one using a 55 gallon drum.

[@randacnam7321]

There is no such thing as centrifugal force. What is happening is that the particles/dust want to keep moving in a straight line colinear with their instantaneous velocity. The separator forces the dust to move in a circle, and this slows the dust until it no longer has sufficient speed to remain airborne, at which point the dust drops into the collector bucket. /engineer

[@pointer2null]

You're sucking air out of the centre of the cyclone - at the lowest pressure point. Would it improve things if you used more of a cone for the seperator, so as the air moves to the smaller end of the code it's forced into the central area and extraction point?

[@Nevir202]

I am curious, if you redid the fan in such a way that you only had blades near the very outer edges, would that be able to keep the airspeed on the outer rim up enough to separate while allowing the air to calm more in the middle before leaving the cyclone thus maybe improving efficiency?

[@RoborobsComputers]

Did you by any chance think of doing the top in a cone shape as this would allow for better flow without decreasing the performance?

[@The_Matrix_Has_You]

Matthias, Did you try to use more smooth matereal for separator. It posible to lose some power when friction is too hight.

[@dumle29]

Александр Сузанский In this case, resistance on the inside would help get better suction. His problem is that the air is spinning around way to fast, causing it to have a hard time getting to the center. If there was some friction in the seperator, slowing down the spin, he would get better suction, as he showed sticking various blocking things in the seperator.

[@jolodojo]

Hi Matthias, i have seen dust collection through a tank of water. Any ideas on how effective that is? Seems more effective to me than micro particle filters.

[@matthiaswandel]

Definitely.

[@darkokomi]

as I see, you made a mistake when you put the suction hose to the rim of a Thien Dust Separator.You have to put the suction hose closer to the center of the separastor, and wind resistance will decrease, and the suction will increase.

[@jumpleadsx2]

I am wondering if the flour that you found in the bucket, only fell down into there when you turned off the airflow. In other words, does the airflow hold the lighter particles on the side of the cylinder?

[@nlo114]

Hi Mattias, You can get a big increase in flow from having a volute on the overflow at the top. Easy to make, it converts the fast-spinning air motion into a straight-line, without the lossy turbulence of a square box-duct. Have a look at < www.scielo.br/scielo.php?script=sci_arttext&pid=S0104-66322007000100008 > It's a bit 'techie'; I just looked at the pics and estimated dimensions for my own build.

[@sergiomorex16]

you should be working in a hadron collider

[@collectorbob810]

try a speed control for the motor. see if slowing it down changes anything

[@robot797]

cant you put a spike in the middel to guide the air up and rounded walls on the oudside doeing thesame

[@heckyes]

Awesome. Never knew about his channel! It's great!

[@kadubmx2]

Maybe you could use something like our respiratory system. Before the air reaches the lungs, it needs to get turbulence.