Comparing three different tower fans to regular desk fans and pedestal fans, evaluating their ability to move air. The Dreo fan I used was the Dreo Pilot max tower fan Get the fan using this link: woodgears.ca/dr/tf
actually its flawed, fan is lifting itself a bit when producing thrust because its moving around a pivot point which is short, you might think its neglibigle, but thrust to weight ratio of those fans is so low that I think its not negligible at all.
You promised to hire that young guy that faked your style a while back next time you went AWOL - I hope his contract is signed and his first upload to your channel is coming soon ;-)
A question remains - if it moves "10 times the air at 1/10th the speed because of conservation of momentum" then how does it fill the bag faster? 1/10th of 10 is 1.
@@tmmtmm maybe there's a kind of saturation effect. If you blow on the same spot always, air will stack up and exert back pressure and push air outside again. If air blows at the complete cross section, there's no such effect.
@@tmmtmm idrk but i think its because when u blow it inside like the first test, the energy is wasted by bouncing hard off the back of the bag and de-cohering into chaotic swirls. when u blow further away it can turn into a big slow moving sort of piston that can push all the air thats already in the bag and turns the energy that was a quick bounce off the back of the bag into a gradual softened push of all the air already in the bag. so it turns the energy into something thats harder to be wasted in the back of the bag when it just becomes swirly. also i think the piston effect helps it go faster because it can fill it faster than the air is even moving by pushing existing air already in there.
When it comes to tech reviews this channel provides a wind of change! I also appreciate the gusty move of going all wood solution for thrust-o-meter. Ok ok, to weather the storm..! I know I spelled it wrong! I don't need to try to be a blowhard, I think it comes naturally..! 🤔 Oh, wait...
Thrust, not only against power-draw, but also vs. noise-level. Alas, too "grindy" a test for MW, I suspect.. Perhaps this is something for ProjectFarm instead..
I actually bought this Dreo fan a few weeks ago from seeing your coverage of their Air Purifier, and I have to say I'm not disappointed. One thing you didn't touch on too much is the noise level, but I can't believe how well it blows for being quiet too. I like the white noise when sleeping, but in my office I appreciate less background noise
I love these videos, feels like a sequel to your one a few years ago about the best fan placement in proximity to a window. Very interesting and truly useful information for those who are technically inclined.
As I posted on your other video, your Dreo talk was enough to get me to buy... and I usually don't jump at buying sponsored content products lol. But I love that it's able to be set in a corner and perform virtually as well as a propeller fan, and look much better doing so.
This is data about which I’ve been wondering for quite a while, but for which I never took the time to make the necessary experiments. Thanks for doing the work and for sharing the results!
Although it was briefly discussed, evaluating the series of fans in regard to a ratio of some sort such as thrust to overall noise (turbulent flow, motor hum, etc.) may be interesting and potentially useful in helping decide which fans may be more appropriate or desired in particular scenarios; e.g summer workshop vs studying area or office in which zoom conferences may be held and the fan noise might be bothersome
I agree too, but the problem with the Dyson is that it's noisy not quiet like they claim, unless you have it down on a super low setting which makes it pretty useless, hence a ratio comparison would have been good
I guess each fans have their good & bad. Seems like it’s an issue that manufacturers are seriously looking into as nowadays you can get traditional desk/pedestal fan with propeller blades that have like 30 speeds & a brushless motor. I feel like tower fans never really catch on because of their weird wind pattern & the fact that they generally can’t point up & down, but I think Dreo is up to something here. I’d still take a traditional propeller blade fan over tower fans any day though.
The tower fans are also a centrifugal type which seem to be favored for producing quieter white noise. My fancy air purifier uses this type in combination with a resin-packed brushless motor and you can barely hear it. I like the vertical form factor. Would actually buy this Dreo model if it came in white.
I like a tower fan because of large vertical area of air moved. It can set behind my desk, and it blows on all of me, legs and arms. It doesn't need to cover a wide area, and doesn't even need to oscillate. The room doesn't need air moving. I'm just after accelerated perspiration evaporation.
Really love this kind of content. It's obvious you are very intelligent, with how you construct all your tests, so it makes for great trustworthy content.
This is a mad genius video... I bloody love it! The only thing missing (and something VERY important to me) is noise level too. If you had included actual db levels... this would have been hands down the most amazing fan video on all of RU-vid!
Well this little ad campaign has worked. Amazon listing the fan as out of stock right now. Oddly quite important for me is whether you can turn off the display. My wife won't sleep with a fan emitting even the slightest light! Great test - well thought through, as always
Fantastic analysis. Now what I want in an office environment is usually for the air around me to be exchanged with fresh air gradually and quietly. I imagine a steady laminar flow would be ideal. I wonder how these fans compare in terms of turbulence.
as you were touching on, the problem with traditional propeller style fans is that they usually have 3 settings, and even the lowest one blows really quite hard. Often one just wants a nice gentle breeze. I use a towerfan with 8 settings, much nicer. It also has an ionizer which is surprisingly good at neutralizing bad smells like smoking neighbors.
Great demonstration with the trash bag. I've sort of some to the same conclusions as you by anecdote. Back in my old shop we had a big barn fan and a large industrial stand fan. Even though the motor hp was about the same, the stand fan seemed to move a lot more air despite it's smaller blade size. It seemed to me then that the velocity of the air was as important as raw volume, and now I can see why. Those Dysons are just not a good deal unless you want a filter in that particular form-factor. I still use the cross flow fans where it fits in better, but the propeller style fans are what I go to now. There are even a few premium ones out there with nice high quality brush-less dc motors and extra-low speed settings.
Did you know the Dreo fans were actually good products before accepting their sponsorship and doing these videos? Or did it come as a pleasant surprise?
@@texnkid Oh that wasn't the intention at all. I just thought it was interesting that of all the crap people promote on youtube, Matthias managed to get behind something that is a good product, and demonstrated it so empirically. In fact if I were in the market for a fan like this I'd just get the Dreo lol
I'm curious about thrust per decibel, as well as wattage at the lowest settings. Would be nice to have a quiet circulating fan that uses as little power as possible. Dreo was totally off my radar, except that I remember seeing their Amazon reviews were absurdly good. Nice to see that your conclusion matches the reviews.
Finally, someone using thrust (!) WELL DONE! Would love to see how the old Westinghouse high pitch propeller fans in the shrouded cases with radial inlet guide vanes would fare. Their tiny 8 or 10" would blow a silent breeze 20' away (!) Also high velocity propeller Honeywell and Vornado.
I used a three phase industrial motor and a attached a huge belt drive wheel to the spindle and then used a belt on a smaller adjacent belt drive wheel with a fan blade attached..... needless to say the wind blew the window frames off my sill but the suction was mad.... paper would fly out of other rooms and stick to the cage.... unbelievable!
Matthias, you have been reluctant to get into sponsorship arrangements for a long time, luckily Dreo has product with suitable qualities and capabilities worthy of your involvement and, with thought, made both entertaining and understandable enough that your audience approves. Now, if only, some intelligent mice and manic marbles could be added into the mix.
Bought this fan and returned it immediately. Fan had a grinding noise that could be heard at all speeds. Never spent so much for a fan before, figured I'd splurge and was immediately punished with a defective unit. Not going to bother with a replacement, just going to get my money back and use what I had before.
I would have loved to see the wattage taken up by each of these. Particularly the Dyson. I'm doing research with a similar type of system and as far as efficiency is concerned im wondering what the force per watt of power is. As in, is it REALLY multiplying the air in a meaningful way that translates to increased reaction forces on the fan?
Should't the thrust experiment take into account the weight of the fan itself? The force produced by the thrust is actually lifting the weight of the fan at the same time as It is acting against the weight scale.
The platform can't actually move much while it's coupled to the scale though, can it? Aside from whatever flex there is in the coupling itself and the surface of the scale.
I don't think it makes much difference, as the fan only moves as much as is needed to measure pressure at the scale. And that will be a maximum of one millimeter.
It should. The swing configuration needs to move backwards to push on the scale. While the scale provides the same amount of resistance, the swing is not going to work the same. A very heavy fan could probably produce Dyson levels of airflow while giving no thrust measurements in this setting.
@@matthiasrandomstuff2221 Wouldn't the fan's weight still cause a slight counterforce to the movement measured by the scale? It's nearly moving horizontally, but there still is a tiny bit of vertical movement given the swing design. Likely the easiest way to be sure would be to place a few bricks on the swing with a fan and see if the measurement changes much. It might be negligible, but I'm not good enough at estimation to say for sure that the weight couldn't affect such a small measurement. Great video as always!
I use a tower fan on its side with furnace filters for my air cleaner in the shop, it works quite well. The varying speed setting they call "breeze" on mine. Now I need to pull the fan off the window a bit. Do you think the screen plays a part in the distance?
I wonder how each would fare if you measure the thrust-to-air speed ratio, would you get a linear performance? Or will the fan design play an important factor at generating higher speeds at lower thrusts.
I think in this case it's likely a 2nd order effect. Some of the force is used to lift the fan as the swing arm moves backward, but since that displacement is very small (restrained by the platen of the scale) the effect is correspondingly small and can be ignored. But your question does suggest an alternative way to measure the thrust. If the swing arm was unrestrained, one could measure the displacement and compute the thrust accounting for the fan weight. This, however, would not be my first choice of methodology.
Im not sure how much it would change the results if any, but removing the front cage of propeller fans drastically changes the airflow. Im not sure how much removing the backcage will do. I keep the back on in case something falls on it.
The Xiaomi SmartMi Smartfan series is definitely among the best and I'd say better than your top pick, it had 100 adjustable speed settings on the higher end fans and can be battery powered so you can use them wirelessly if you want. Also cheaper than $100. Use mine in the bedroom all the time.
Interesting thrust measuring device - I'm curious if there's any torque/moment concerns. basically wondering if a fan closer to the floor performs differently on your rig than a tall fan on a long leg stand would. (I assume the answer is it would be the same with or without the leg, but I'm not 100% sure).
Yeah I was thinking the same thing. If you take it to the extremes and use a really tall fan (or a really flat fan) the thrust will vary because of where the force is coming from in relation to the pivot point.
Hi Matthias, just discovered you just now with the Fan series. I had for a long a question in mind regarding fans that maybe you can test out if it gets you curious: When sleeping, how do I get the best airflow in the room ? 1) The fan blows from the floor directly towards a wall (can try a side wall and one opposite to the bed). 2) The fan blows from the floor diagonally towards the ceiling (can try towards a flat wall and towards an upper-corner). You might get other ideas of positions (towards the floor ?) and directions in the process :D. My personal feeling was that towards an upper-corner was best but I might be wrong !
Very interesting video. If you do another video on this you should try to graph out thrust vs decibel or calculate grams of thrust per decibel or thrust per dollar to see not just the flat out most thrust but most bang for buck or the most efficient while still being quite
Cool video... 😁. I think an important measure is volume of air the fan moves, not simply miles per hour. Probably need an expensive lab to determine cfm, cubic feet per minute of air volume moved.
is the weight of the fans accounted for in the measure of thrust? i imagine if it's heavy, it sort of reduces the measurement at the scale as there might be a change in height of the fan based on the rig you've set up.
Nice job! Would you consider measuring thrust over loudness? Side note: the air filters seem like a silencer that they made up another reason for including.
Does the mass of the fan make a difference with your thrust measuring setup? I'm curious if you would get the same measurement if the fans were set on top of weights to normalize them.
doesn't make a difference. The fan doesn't actually move back because the scale prevents it from moving back. Also, I tare the scale to zero before the fan is turned on.
Is the Dyson's thrust low because the fan is acutally pushing air up, then 90° foward? Also I would think that this setup hurts efficiency? But it connects to my Wi-Fi! 😅
Wish I had a certain box fan I had as a kid. It used a round body that was closer to the propeller and did way better than a cheap box fan. Unfortunately, it was also entirely plastic and not very drop resistant.
The dreo is a pretty nice looking fan, I would consider using it in a place where using the cheap propeller fan would look unprofessional, like in the reception area of my office. It would also look much nicer than the comparable propeller fan in my living room
Thank you for the insightful video. I would be very interested in small personal fans (portable desk fans) equivalent, not just thrust but also noise levels would be great to measure. Are you planning something like this?
Would the mass of the fan affect the thrust measuring system? It seems like some of those fans are really small, so they might also have very low mass compared with the big fan. But on the other hand, they're mostly plastic, so it might be the case that the motor makes up so much of the mass that the size is nearly nothing in comparison.
Based on your previous videos, squirrel cage fans suck in air from sides, plus have some funny turbulence. Vs propeller which suck in from the back: doesnt that affect thrust?
You should do these same tests on the dual window fans (the kinds with two fans that can blow air in, out, or both). Be careful, because not every kind of "dual window fan" has that last setting. Some can only blow in or out.
