Tower fans are kind of weird

I have always wondered what makes the vertical blower drum in a tower fan blow forward as opposed to any random direction. Playing around with a physical model, I observed some interesting behaviour.
The Dreo fan is the Dreo Pilot max tower fan
Get the fan using this link: woodgears.ca/d...
15% discount code for Dreo website, valid until Nov 15 2022: 9RP733E2X9Z0

[@nefariousyawn]

I'm a long time viewer, and you have managed to make some of the most interesting sponsored videos I have seen on KZbin. I hope these types of videos are paying off for you.

[@jackharper24]

i bought the air cleaner he did a video on the other week, its v nice. but only because hes matthias would i buy anything from youtube

[@Sibicle]

agree! really cool that you found a sponsor that you feel you can support without compromising your integrity. and hey it seems like they actually make pretty good stuff too! will probably check some of their products out ^o^

[@eugenetswong]

I agree. It's weird that it all works so well together. I'm so very impressed.

[@landonkryger]

Now I'm really curious and want to see a smoke machine with them all to visualize the flow better.

[@BLX187]

i thought the same.

[@cryorig_transit05]

I agree

[@coreydolan]

I never thought about how a tower fan actually worked....now I understand it's magic

[@ddegn]

This is my conclusion as well. Now the question is which kind of magic? I think it's likely *Voodoo* or possibly some form of *Druid Magic.* Hopefully the next video will let us know.

[@FantomMisfit]

Warrior of Chaos: Beyond your comprehension

[@CogitoBcn]

It would be even more amazing to see the block/cage interaction within a smoke generator.

[@DamianReloaded]

I imagine when the air starts flowing in one direction it must create a low pressure on that side that forces incoming air into filling it. The block of wood must work like a wing, creating a pressure differential.

[@PierreJullia]

Agree. The comparison of the block of wood with a wing is quite relevant

[@Keifsanderson]

I appreciate your sponsored content just as much as your original project videos. Thank you.

[@Keifsanderson]

@Milan Velky 😆

[@Quitenice]

More sponsored content like this please, never thought about how these would work. Now I am wondering why not make them diagonal ❤️😊

[@Tomazack]

Less space-efficient I imagine.

[@drewg8710]

Prasanth! Another of my favorite channels

[@Scrogan]

By diagonal do you mean have helical blades instead of vertical ones?

[@rjamsbury1]

You just made a switchable bistable with that fan! I'm now imagining some sort of mad circuit with fans controlling other fans' directions 🤣

[@Pixelarter]

A fan computer!

[@jenniferpearce1052]

Rube Goldberg materials!

[@willhaney96]

@@Pixelarter its a sr latch.

[@birigoboom]

There must be “pockets” of air circulating that is trapped around the squirrel cage. That block of wood disrupts it, permitting such movement. This is pretty fascinating for a layman. I’d like to get an physics/aerodynamic explanation of this.

[@TheChipmunk2008]

I wonder if it might be worth asking the action lab... Or Steve mould

[@custos3249]

Agreed, but Mathias probably got close to the actual aerodynamics. Really would've been cool to see a smoke test to look at the flow characteristics. At a glance, I'd have to wager it's probably either that, as the cage spins without the wedge, it creates vortexes on the outside that process around and away from the cage as it spins kinda like planetary gear set, and as one hits the bag, you see the bag flutter between moments of high and low pressure. By placing the wedge, it both blocks that procession and biases the output which then also biases the input. You get a high pressure zone at the wedge and a low pressure zone on its other side. It's basically just how some floor vacuums work - or at least a couple I've taken apart. Or its all about turbulent flow. There's just enough points of low pressure in the cage, air is able to circulate due to centripetal force providing enough impetus to outflow, but the wedge has more or less the same effect in organizing flow.

[@blueberryadept6519]

Would really love a smoke test with this one to better visualize it!

[@ratchet1freak]

smoke visualization would be amazing to see I'd think

[@unitrader403]

maybe someone can make a Fan based on this for the Fan Showdown :D

[@ChannelSchen]

THANK you! I've been searching for half an hour for an actual explanation of why these fans blow on one side and not just equally all around. Finally, I stumbled upon your video, which makes perfect sense, and kind of confirms what I had guessed at myself (that the positioning of the vents sets up some kind of high-pressure/low-pressure imbalance that pushes the air through.) I certainly hadn't imagined that it could be switched from one side to the other on the fly like that. So that was pretty amazing.

[@FarmCraft101]

Not sure how you pulled that off Matthias! Making a video about a fan? Kind of like making a video about paint drying. But sure enough, interesting content as always!

[@Warrigt]

Technology Connections would like to have a word about 30 minute videos on mundane things.

[@meeponinthbit3466]

He done wood drying.... Sure paint will come one day with humidity and temp sensors using an Arduino. kzbin.info/www/bejne/oZSqhnqJaaaUf5o

[@Wordsnwood]

Not the first time, sir. Don't you remember way back when the lawnmower videos went out there? I think Matthias started that, and then Jimmy Diresta copied, and I forget how many other makers followed suit.

[@leonclose7823]

Surely he's done paint drying already? This type of stuff is why I'm here.

[@meeponinthbit3466]

@@leonclose7823 he's done some painting..... But can't find any science on the drying.... So new video idea? 💡 kzbin.info/www/bejne/Y2G7m2uHgs99iJY

[@_P0tat07_]

That’s so cool! Especially how you were able to change direction of how it was blowing. I’ve always wondered what made these fans work

[@Lizlodude]

Wat. I swear, you have some of the best sponsored content. And that reflects well on the sponsors that they're willing to let you do things like this or take their stuff apart. Also we definitely need some smoke and simulation analysis on how the heck these fans work, that's pretty cool and not particularly intuitive, most I've seen pull from the top as well.

[@ionstorm66]

You always do the best sponsored videos. Informative about the subject, and good real world testing on the sponsored item.

[@dallen521]

Thank you Dreo for letting Matthias play around, productively, with one of your products. I found the video has raised a whole bunch of questions. Look forward to the next one Matthias.

[@BuddyCrotty]

I just watched a 5 and a half minute commercial about a fan......and can't wait for part two!

[@setSCEtoAUX]

Thanks for this. I've been puzzling over how my tower fan worked ever since I got it (though not enough to try experiments). Now I'm left to wonder how they were invented. Someone noticing the effect on accident, or someone with good understanding of the fluid dynamics that realized it could work before building it.

[@matthiasrandomstuff2221]

I would guess by accident. These things have been around much longer than computational fluid dynamics.

[@anxiousdog]

Finally. I’ve been wondering how the design looks inside ever since i peeked inside my mini split 3 yrs ago.

[@Makstuff]

Dreo fan on amazon: Temporarily out of stock. Either something went very wrong or very right :D

[@matthiasrandomstuff2221]

out of stock for canada, not for USA

[@O8532732]

Probably be in stock on July 1st to avoid paying a dime for the promotion. 🤔😂

[@Bpdiericks]

I’m glad you test the products that you do sponsored videos of. It shows the sponsor has faith in there products and your showing comparatively how good the product is not just telling up its good. Thank you.

[@Xaqaria]

This is a good type of sponsored content. They don't have that JD Powers and Associates "vote the shiniest bumper for the last 5 years" feel, either.

[@jamesdlin7]

When you do your performance comparison, I hope you measure air flow relative to noise. Most air moved for the least amount of noise is usually what I'm most interested in.

[@ratchet1freak]

I never turn my fan up to the point I can hear it, low speed on fans is highly underrated

[@mrfrenzy.]

Yeah, just measuring the wind speed is not enough, it also depends on how wide and high the air stream is.

[@promix49]

Thank you for your effort, it's interesting that the air flow direction has to be "initialized".

[@qorje]

The only sponsored video on the internet that I don't stop immediately... It was quite interesting!

[@TheZakimus]

Dreo made a really good call on sponsoring you in particular, you've made legitimately interesting content around them, really appreciate that

[@itinerantscientist8502]

Thanks Sir for such a great explanation. Experimental setup is astonishing!

[@MrCheesywaffles]

Wonderful demonstrations of the flipping back and forth, really suprised me with the compressed air. Well integrated promotion, showing the fan off while keeping it interesting

[@nadravface]

Latching fan, can work as a memory. Imagin computer based on small fan units with small fins changing its state

[@MrThedennisblack]

For what it’s worth, I’ve never bought something from a KZbin sponsored video before, but I ended up buying two of these Dreo fans. I bought one first, and loved it so much that I bought another one. I like to run my fans at a low speed, and when you run these Dreo fans at their low speeds they are literally silent. I’m not joking. I cannot hear them at all at their low speeds, yet they’re moving plenty of air for me to feel comfortable. They are pricy, but in my experience they are worth every penny.

[@gblargg]

I like the end where fan noise levels are compared. Tower fans really shine in this regard. I want that Dreo Pilot max tower fan but it's pretty expensive.

[@covariance5446]

Most youtube videos (in my experience) have titlies that oversell how interesting the content is going to be. This is a case where the title is a complete understatement re: how interesting the content is!

[@lennart637]

I have a tower fan, because it reminded me of the cross flow fan in the heating/ac of my car.

[@Srt8Jeep]

It’s comforting to know I’m not the only one that lies awake in bed thinking about fans and air movement.

[@k.medeiros1983]

This is similar to high lift blades on a commercial lawn mower. If the mower gets clogged a bit , it will affect the discharge direction

[@Nbomber]

Ive always wondered about this, and this is me finally deciding to find out. My best guess was some kind of enclosure shape magic. Super clever.

[@cubbucca]

wow, just what i needed. your demo makes it so clear whats going on with the air flow.

[@johnfisher4910]

Would be amazing if you could continue this sort of sponsored content - just as long as you can be completely honest with your review. Thanks for sharing!

[@danielthechskid]

I call these tangential blowers. I have a small one taken from a dead scam cube heater that I replaced the C frame shaded pole induction motor with a brushless DC motor and now it is low voltage, portable, and variable speed.

[@Deckzwabber]

Thanks! I was trying to ask this to the person at the shop where I bought my tower fan, but I couldn't even get them to understand the question.

[@matthiasrandomstuff2221]

The Dreo fan is the Dreo Pilot max tower fan Get the fan using this link: woodgears.ca/dr/tf 15% discount code for Dreo website, valid until Nov 15 2022: 9RP733E2X9Z0

[@FairySushi]

Disclaimer I haven't done fluid dynamics for 3 years or so, but here are some quick thoughts: I think perhaps the addition of the block next to the squirrel cage has two effects. One it breaks the symmetry of the air flow and turbulence around the cage; without the block there's a lot of vortices symmetrically around the cage and the streamlines stick to the circular cage. By breaking the symmetry and importantly adding that let's say ramp for the streamlines to shed off of, air can now flow away from and off the vicintiy of the cage. This is why you get faster flow of air in a single direction, I think. When there's two blocks symmetrically around the cage it really comes down to (luck/) the tiny microscopic differences between one ramp and the other since flowing from either side is a stable configuration - think similarly to if you placed a ball perfectly on top of a wedge, it's going to fall off but really it's just a matter of chance which side. By blocking one intake or the other you then forcefully remove one of the possible stable states so then it flows in the direction that's left. For the fireplace unit blower and adding the block; another factor in why the air moves faster might be because you're restricting the cross-sectional area for the air, but the volume rate of change is still the same, so if the area is smaller then the velocity outwards must be bigger. Similar to gripping a water hose to make the water go out faster. I'd love to hear other's opinions on this!

[@ronski50]

The fireplace fan is riding the fan curve (resistance/static pressure vs air flow). This is a forward curved blade centrifugal fan, the added resistance of the piece of wood brings the fan performance closer to it's peak efficiency.

[@Metalcastr]

There was a window fan sold a few years ago that used this principle, the Lakewood LPRW3 with dial controls, and LPRW3-D with digital controls. It had a physical lever to direct air inward or out, without changing fan rotation. In many ways it was the best window fan, but is not sold anymore. There are other blower-style window fans on the market now, but they're marketed as premium models with prices near $100. Also there seems to only be two blower-style window fans that I can find available in the U.S. as of June 2022, the "Sharper Image Portal XT" and the "Vornado Transom", both of which can electronically switch between intake and exhaust. I'd like to see how they accomplish that, if it's some kind of moving actuator redirecting air, similar to how it was done in this video.

[@billkurek5576]

All I know is only Matthias could get me to watch a 5 minute promotional video all the way. Excellent, thanks

[@ThorWedd]

Have a NZ made fan heater with the same fan setup - horizontally mounted fan. 1982 production year Always wondered why it seemed to ran backwards sometimes

[@eVITORIOe]

My bet is that the block introduces a pressure difference. Air hitting the block directly creates a high pressure zone and the region right after it decreases in pressure. Air flows to the low pressure zone naturally.

[@ohtrueyeahnah]

This dude always makes good videos that I didn't know I was interested in.

[@confuzionn4843]

I like the sponsored content where you take their stuff apart. Shows the company is confident in their engineering... or ignorant enough to just not care what people find.

[@nathanlucas6465]

Assuming these people know what you're test vids are like, sending it to you really does show that they've got quite a lot of confidence in their product

[@Mike81111]

I always was wondering how on earth these work. I have small heater for inside of the car and I just couldn't understand how it was possible to work. Thanks to you now I know!

[@LeesChannel]

I didn't mind the occasional relevant sponsored video previously, but now it feels like they have taken over the channel.

[@brandonrunyon]

Matthias manages to find where the angles of interest are in even the seemingly mundane of devices. I'm sure the engineers that make these innovations can appreciate his analysis.

[@zodiacfml]

interesting. i think the reason the small block could to that is it creates a high pressure and low pressure sides. the low pressure side of the block makes it mostly the sucking side of the the fan. 2:13 well this matters because there is no way for it to get/suck air except from its top/open side. smoke testing could reveal some of the operation

[@AronGreen]

The only sponsored videos I've enjoyed on all of KZbin! :) I love the science behind this stuff. Also, it would be interesting to try a smoke test with the squirrel cage fan and see if you can see exactly what's going on.

[@davidmcgrath6507]

Brilliant!

[@bobd.]

Very interesting, I never would have expected the air flow to react like that when you introduced the wedge. It's a simple way to reverse the flow on the fan with one moving part.

[@sb1349]

Have been wondering how tower fans have worked for years. Thanks for the explanation.

[@JW77]

I don't know why but I think your sponsored videos are fine. I don't mind them at all. I actually enjoy them quite a lot.

[@DEADB33F]

This is how to do great sponsored content. Good job. I hope the companies who sponsor you appreciate it.

[@meeponinthbit3466]

Of course he turns a friggin fan into a sponsorship and cool lesson.

[@graealex]

That was very interesting. I integrated these kind of fans in industrial applications several times, but I was not aware that this is essentially a dynamic phenomenon.

[@JoseSilveira-newhandleforYT]

Very interesting test and really weird behavior of air flows. And that Dreo tower fan has some impressive output!

[@by14996]

What's really cool is Air is actually a Fluid!! And therefore obeys fluid dynamics! I am sure you knew that Mathias, just pointing it out. :)

[@MisterAJ12]

All your "fans" gathered in the same room I can add that i am a huge fan! You blow me away with this video

[@timfischer]

I think this is the first time I've watched a video about a sponsored product and then immediately went out and bought it. The $26 credit was a nice bonus, and the fan seems very impressive. Tell your sponsor that the video generated at least one sale lol. Mine comes on Thursday so I'll be anxious to see how well it works.

[@rklauco]

It would be worth to do high-speed camera airflow video with some colored smoke... I wouldn't have guessed that the topic will be so interesting. Congrats on taking a mundane object and discover the level of engineering behind!

[@XtrmJosh]

Possibly the only kind of sponsored video I don't dislike watching!

[@recklessroges]

I didn't know about that ability of squirrel fans. Thank you Matthias for showing me something that is new to me. Sponsor, "Out product is made of plastic and metal." "I'm testing it with wood!!!"

[@charliewynn3210]

Being able to control which side of the cage it comes out of reminds me of Matt Parker's domino computer. With patience you could maybe make half adder

[@CJsKanal]

Diese bauart von Gebläsen wird auch in vielen Mähdreschern verbaut. Zum Reinigen des Dreschgutes auf den sieben wird ein breiter und vorallem gleichmäßiger Luftstrom, der von unten durch die Siebe nach oben srömt benötigt. Somit werden Spreu, Staub und Kaff nach hinten in die Spreuverteiler und somit aus der maschiene geblasen.

[@thorable530]

There were even blower fan addons for pcs that would blow into 5" drive bays, but the bearings would go out too quickly.

[@rolliebca]

Enjoyed this preview immensely. Looking forward to the in depth version as only Mathias can do.

[@Teth47]

I think this is a boundary layer effect. The inside of the rotor is not engaged with the air in any meaningful way, and I even suspect that a solid rotor with no holes would perform similarly. I suspect that the block of wood is literally just shaving the high velocity air entrained around the spinning rotor away at that particular point, creating a pressure gradient that favors air moving toward the positive tangential slope of the obstacle. This could be tested by wrapping that squirrel cage blower in something to seal it and trying again. Maybe a grocery bag and some elastic bands.

[@tullgutten]

Always wondered how these things worked as they are used in split ac units and ive never seen any side intakes 😅😂 Thank you for this video 😁👍

[@profile5]

Never watched your content before, this video is great.

[@ballbagasaurus]

Have to be brave to give your products to Matthias, he will literally tear them apart. Love these REAL sponsored videos

[@practicalguy973]

Very cool technology on the Dreo. I have the Ridgid 18V Hybrid Fan, it also has a lot of interesting fan technology. There is a ribbed design on the fan blades that makes them quiet, it's small but decent 475cfm, variable speed, can be aimed in almost any direction. Set to about 20% speed I can hardly hear it and feel the air still from about 15 feet away due to the vortex the duct and grill create with the air. The hybrid design is great, on a 4ah battery it will run all day on that setting or take the battery out and use a standard 3 prong extension cord. This being a shop fan is not in the same category as the Dreo but these type of shop fans are something you can also make an interesting video on.

[@hikingpete]

I don't usually watch sponsored content, but when I do, it's Matthias random stuff.

[@instantmuffin5]

My initial suspicion was that the case design creates an imbalance in pressure which makes it easier to suck air from one side, or push it out the other. What you do is, you deflect a part of otherwise homogenous airflow and direct it outward, thus tilting the pressure balance and jump starting the airflow direction. In a way it is very comparable to the way specific types of motors work.

[@instantmuffin5]

That said, you do have airflow directing fins on the front and just holes on the back.

[@instantmuffin5]

Oh and when comparing the output you should factor in motor power and angular width (and height on some models) of the airflow, also the area of the exhaust.

[@pennyroyal3813]

I've been a fan of Matthias for years.

[@gamingSlasher]

Very interesting construction. Didnt know it worked in that way.

[@Viruzzz]

If it wasn't for the fact that dreo seems to only be marketed in the US and I'm Europe, I would actually consider some of these products. It does kind of say a lot about their confidence in their own product that they are letting someone who likes to tinker play with their products rather than just having someone read out a list of talking points that doesn't really say anything at all because every other similar product is saying the exact same things.

[@sprint955st]

The white tall one in the centre….that’s your biggest fan right there

[@MiscMitz]

Neat. Never thought about how they work.

[@spugintrntl]

3:00 that is SO FRIGGIN COOL.

[@katelights]

interesting stuff. the only way to improve would be if you had a smoke machine to visualise some of the air currents :D

[@thatguythatdoesstuff5899]

I pulled a fan like that from an old kitchen oven and wondered where it was sucking the air from. Very interesting. Now I just have to find a use for the fan. I'm open for suggestions.

[@aserta]

I imagine the blocks of wood (or any stopper) are kinda like an on - off ramps for air. Kinda...

[@ecsyntric]

thought i knew about fans then a totally alien concept drops out of the sky

[@atomicsmith]

I love these odd experimental videos.

[@MCsCreations]

Fantastic experiments, Matthias! 😃 Stay safe there with your family! 🖖😊

[@Scrogan]

Exactly the kind of sponsored video I’d expect, one that actually teaches something. I’d quite like to see some sort of idea of how directional the fans are in comparison with one another, there’s a few ways to tackle that issue. Also I hope you use the good old “how long to fill a garbage bag” test so we can see actual airflow, plus a power consumption comparison. I’d be surprised if it came out to be more efficient than the standard airscrew design, but these initial results are promising. If you had a 3D printer you could do a bunch of fan geometry tests (or do machine learning iterative simulated fan design) which might be interesting, though I know the former is being done to some extent already here on KZbin. The unexpected directionality reminds me a bit of the Magnus effect.

[@JoeGP]

the high wind speed is actually a disadvantage if you ask me, since i haven't seen any fan that doesn't blow way too hard even on it's slowest setting, so why the extra speeds exist i have no idea. Would be nice too see a video on how to slow them down

[@holynex]

What kind of sorcery is that? 😱 Doing a good job I guess. No units left on amazon! 😊

[@johnarnebirkeland]

Never thought I would see Mattias make fan service videos.. :)

[@Gersberms]

What I like is how they move a ton of air with a very calming rustle, not the nasty chopping sound of a three blade fan.

[@gannas42]

Very nice demonstration of how, what I assume to be, a low pressure area affects that type of impeller setup! On a side note not sure if I'm just getting old or what but the cost of goods these days seems ridiculous to me. I followed the Amazon link and kinda went meh, I'll just be warm instead.

[@matthiasrandomstuff2221]

tower fans are more expensive than propeller type fans. Just get an old fashioned fan.

[@mattf9096]

This company has to be pretty confident in their tech to ask Matthias to sponsor them. If it were shit he'd figure that out pretty quick.

[@x9x9x9x9x9]

That is more weird than I expected. I understand how it keeps going in one direction but im just not sure on the aero dynamics of how it starts in that one direction.

[@sixtofive]

Venturi effect sucking air into one side due to lower pressure? Basically how lift works with an airplane wing.

[@fergusontea]

The red bag Matthias is using is a bag that held 3 bags of milk. Canadian trivia. :)

[@Loneman_OG]

I'd like to hear your opinions on pedestal vs tower vs large box fans. In the UK, most people seem to have shifted from 12"-18" pedestal types over to tower units, the latter seemingly weaker but quieter, have better æsthetics plus, they're typically remote controlled. 18"-22" square box fans are either nonexistent over here or extortionately priced, or even worse, on occasion, shipped in running off 110VAC! 🔌⚡💥😵