I think what you should be measuring is, the minimum air speed required to turn the generator, and whether it will still turn under load. I think your fan blade will turn with less real breeze and will continue to spin under a much greater load. And if I am not mistaken, with a long shaft it would convert well to a turbulent vortex water generator. Anyway, the fan was very ideal source for the stock pc gen.
Loads of things could play into that result: Weight, number of blades, the housing.... but as a simple, cheap, easy and effective test-rig, it can't be beaten!
Thank you very much Robert! "Keep it Simple!"!! (KISS!!) is a Splendid Motto ~For Myself Especially!! These things are all over the Place and people are forever throwing them out!! It's a Far Better thing,,, ~that we Use these, Rather than Thow them out!! Many Thanks again Robert!!
Of course it does. My experience with auto mechanic jobs has shown me the cause effect of the fan shrouds on radiator cooling fans. The difference of wind velocity is easily double with the shroud installed. Also with a single webber carb on each cylinder the height of the velocity stacks or tube on top sucking in air has a definitive change on engine performance
The small fan matches the size of the hairdryer so is more efficient,creating more RPM, so more voltage. For a more accurate measurement both fans need to be same size.
I will suggest to have an small wind tunnel so all your tests have close to same conditions. But this is up to you and only for you (we all can make our own tests if we want to have "real" data). You have provide the spark to start our curiosity already!
The airstream from the hairdryer was going right through the large holes in the LARGE toroidal propeller. I would make both propellers the same size and both in an enclosure.
the benefit of that MIT propellor isn't so much it's wind speed to rotation efficiency but rather its input wind speed to output wind speed as a motor - if you were to use these as motors and check the output wind profiles, the computer fan likely has very heavy turbulence (which is actually good for its application - heat dissipation), whereas that MIT propellor, judging by its shape, most likely maintains laminar flow (which is good for efficient propulsion)
Thanks for the video: The premise is slightly incorrect: Large diameters don't spin faster, but they do provide more "torque". Probably to make this a fair test, you would have to scale the MIT prop down to the same diameter of the propeller fan. (Or vice versa). One other thing, I have watched some videos on the MIT prop, and I can say so far all of them have been "underwhelming" as far as performance in "Air".
I saw that without any testing. Air turbine blades need their own design because they are removing power from the airflow, not pushing power into it. Large diameter sweep areas always remain the same in the designs no matter how much blade area is added. The numbers are formulas that can be changed to take more or less power from the airstream. With geometry we can add/or remove, more or less blade area to the sweep area. The big question for me is, "Drag?" How can I add more push surface without increasing the drag? Robs' blade that he has designed can easily become a lot more efficient, by changing the angle of the blades to 45deg to the post instead of 90deg while keeping the rise the same, and adding a curve to the bottom of a steeper cone. This would help in the upscaled designed. I also see design solutions for the blades themselves that would virtually eliminate drag. Also as we all see his blade is twice effictive if it is faced into the wind as opposed to a vertical application. I'm a poet, not a scientist. Take it easy on me.👁
Love the touch of Dr. Who in the use of the phone booth as a prop. :) Robert is truly striking me more and more as a real life Dr. Who in the science corner.
Great stuff. Thank you. I've often wondered if the contest done on the RUclips channel "Majorhardware" would work in reverse? They test to find the best fan design for moving air, quietness and things like that. I wonder how good the best ones would do at generation? Just a thought.
If you have a wall of 'hearing trumpets' all feeding into a point, the directed wind current will be amplified to a degree that you should be able to get enough air current to push something that'll generate an actually useful amount of wattage.
At the end the PC fan entire surface was taken up by the blow-dryer whereas the Toronto fan only a portion of it was taken up which is why all the energy was not grabbed by the fan thank you
the voltage is directly connected to the RPM. The MIT one has a different pitch and size, and looks to spin slower. So lower volts is to be expected. but the current output is possible higher. although i think you would get more power out of these generators with higher voltage/more rpm.
I already have a rf 455mhz remote water level indicator at high floor of the building, feed by a solar cell charging a Liion battery, but when cloudy for days I can't take the measurement, I will put one of these fans as generator to have two power sources to charge battery.. Thank you so much for you very didactic videos..
There is a large area on the toroidal fan where the air just bypasses the blades. Perhaps a more complex shape where the loops are interlaced would improve the result. Interlacing could allow for more blades while retaining similar angles to the direction of airflow. An example of the interlacing I envision is the turks head knot although more blades would be an improvement along with the interlacing.
The primary benefit of the toroidal propeller is its low noise generation. You could say their are trade-offs between size, power output, efficiency, sound generation, and complexity. As has been addressed in a previous video "the best design is not always the most efficient." I could see the low sound generation being preferred in areas where you want to keep noise pollution at a minimum.
The hair dryer has a small circle of concentrated air flow, about the size of the small fan. You had it pointed to one corner of the bigger fan. The big one did not come near to experiencing or capturing equal energy. Try 3 time that distance pointed at the center of both.
With very low voltages on each of two coils 90 degrees out of phase, It might help to have a voltage doubler circuit. (Two diode two capacitor) for each coil. Then one can put the outputs of each doubler in parallel with the other. Under light loads it will virtually double the peek voltage (sqrt(2)× rms) of a single coil minus voltage drop of diode.
My suspicion here is that toroidal prop would benefit from real wind scenario instead of the overly small wind profile the dryer offers. The dryer is, I suspect only capturing a smaller volume of that overly focused air stream but against a widened stream (say a large diameter fan) would perform very differently. Just my supposition but it’d be nice to find out
Your hand behind the Toroidal Propeller could be causing a wind resistance and combined with the hair dryer's angle is about 20degrees off center could also cause a reduction in output, but not that much. Back to the drawing board. Another GREAT VIDEO!
what I am wondering is if you could just solder some wires to the points of output with out altering anything else and still be able to use it as a fan or generator based on which wires you are hooked up to, and possibly even hook the generator output wires to a reader so it would let you know when it is running by counting the pulses coming from the generator output the way they do with some stepper motor drivers that use the back EMF that comes from the unpowered coils when the motor moves to know a step in the direction was accomplished (ie it reads the motion) and if this back EMF does not occur it warns the software that the machine has not moved, turning the idea of an open loop CNC system into a complete closed loop system (each step sent waits for a reply to let it know the motion has been moved before it shuts off and sends the next pulse for another step, counting according to the software to reach it's destination, otherwise it will assume a step has been lost, where the machine being bound up causing a lost step in an open loop system will have no idea this has occurred and thus the machine will not know where the cutter (or extruder for 3D printers) is actually at. )
The test result is pretty much expected. The original traditional fan blade have more surface area and density (surface area of blades per area of 12 cm fan) for the air to push. Thus, it generates more voltage.
There is a lot of eyeball visible axial runout as the toroidal fan rotates and possibly some radial that's not as visible. This will rob a lot of the potential power generation potential. A bit more precision at the axle to fan joint might yield some performance benefits.
Hello old chap- I’ve been watching your rather excellent instructorials and I’ve been wondering… would you be interested in doing some on ways to mitigate or counter certain applications’ planned obsolescence?
Wonder if the airflow from the hairdryer is concentrated on one spot, coincidentally the same size as the pc fan - a wider 'tunnel' of air may show different results - enjoyed the video
The torpidal fan was not fully 'illuminated' by the 'wind', whereas the pc fan was pretty much fully engaged..you needed to test at a greater distance from the hair dryer, to get a larger, more consistent air flow, this would have the pc fan experience much less wind energy, amd the toroidal would be more completely driven. As others have commented, there is also the question of deliverable power, since your test is open circuit...consider how aircraft propellors use different pitch to deliver takeoff power with low airspeed, and higher pitch for power delivery at higher airspeed...
Mr. Robert Murray-Smith I would be curios to see the same experiment again but instead of measuring the open circuit voltage measure the short circuit amperage. I wonder if the longer blades on the toroidal propeller are providing excess leveraged mass reducing top RPM and limiting OC voltage but perhaps increasing SC amperage leading to turbines of similar wattage but a preference for higher or lower speed winds. What do you think? Regards, Borel's Monkey #4
You mention a front and a back with the toroidal fan. I have been wondering if they would work underwater as a generator using tidal currents. The Severn has the second highest tidal range in the UK. Thats a lot of water going in and out. So instead of using barrages to store and release water, what about installing something sub surface to capture the energy in that movement? So is there a front and a back? We need a fan/prpellor that works efficiently in both directions. Just a thought.
Is that the same design that they are. Claiming makes for a more efficient marine propeller?. Perhaps the reason it works as a marine propeller is because it's being used for thrust in a denser environment. Perhaps you could do a comparative experiment on this please
I don't think there's any mathematical equation to back up this... but... it would seem like the toroidal propeller has a lot of empty space between the fins whereas the computer fan blades do not. I think for air movement, the pitch of the toroidal propellers needs to be rotated about 90° and needs a helluva lot more fins. More plastic covering the open space and an easier angle for the wind to blow past it... With the pitch being nearly perpendicular to the axis of rotation, that would be really good for moving a slower, heavier (meaning has a lot of mass) fluid rather than a faster, lighter fluid like air or any other kind of gaseous substance. I think you need something a bit more parallel to the axis of rotation.
Possibly the larger diameter of the fan means it can't spin as fast as the smaller one. It may produce a higher torque which needs gearing to get the same revs.
You soldering iron looked much like an old - WEN- 'QUICK HOT' Unit I recently salvaged. The internal design is far more robust in its construction than my recent smoked, made in China iron. I have such high hopes for thi device, but I can't manage to fond or create a tip that will get hot enough. I am determined to revive it, and it seems S though I could run some cables up to a hand held tip rather than having the other kilogram of weight in my hand. Any suggestions would be greatly appreciated. Thanks
Iv recently wondered how much energy you could get from one of those hand warmers. Those ones that have a stick of smouldering charcoal in and that can keep warm for hours. A few peltier jobbies slapped around the outside of that with possibly a water cooling system as a differential engine might work as a small portable generator that doesn't need refueling or stoking every 5 seconds. Maybe with an option to increase airflow with vents should you need an extra boost of heat/voltage at the cost of less fuel efficiency
🤔 Maybe printing the toroidal blade with a ring around it, magnets on the outside of the ring, and the serpentine coil from a previous video? IDK, this video has me stumped. I thought the t blade would have done better, but does it have something to do with RPM vs Torque? I'm so lost on this one 😂😂😂
If the toroidal blade produces more wind, and the standard blade catches more wind, what is the difference in output from wind generated by each blade and caught by the same generator? Hey, I just spent the past week setting up a Linux server, I had to ask a silly question to destress.
At that range the stream of air from the hair drier is focused only on part of the toroidal propeller, and the rest will be using torque to drive more air, thus wasting energy.
Hmm - with these comparisons - needs a variable load (dynamometer) to determine peak power output in a given air stream.... Free stream speed is a fairly low quality prognosticator... (blade pitch governs unloaded rotational speed).
First great stuff. Second. I work for a company that sends out replacement pc fans but none with a usb plug. We have redundant ones every now and then. How to replace the standard (flat) pc plug, Please. Can it go wrong?
I know that you can't user a propellor as a windmill because the 'top' of the airfoil is on the wrong side. Well, you can use them, but they will be ridiculously inefficient. Surely the same principle applies to any propellor/windmill swap?
The outer regions of the toroidal blade is mainly focused for silence, but seemingly not so much for optional conversation of air does to rotation speed. If it was so efficient, we might have seen that design in turning engines already..? With a probably designed static guide blades, a gas turbine can reach efficiencies well above 90%, so that's really hard to beat, probably. The tips of the blades help a lot to reach maximum speed, so the silent trade-off clearly seems to cause a significant reduction in efficiency...?
I think your air flow has about 100% coverage of the frontal area of the pc fan, but probably less than 30% coverage of the frontal area of the much larger toroidal. But you'd still expect the results to be more similar, given there's a similar amount of air moving through both. I suspect the toroidal doesn't work very well unless it has air pressure across it's entire surface perhaps? There's an interesting YT channel which tests novel 3D printed designs for pc fans. Toroidals don't actually stand out in those tests. Also, the cowling shapes very much matter.
I would be happy if a 20" box fan tolaroidal replacement blade went on sale not necessarily to be more efficient just add a little more wind to the situation for funsies
Robert, it lookes like you issed a lot of the tiroidal fan with the smaller dimatior of the hair drier output. Try this again with a drive fan that is larger than the fans under test, you will not miss so much of the fan you are trying to drive. aLex..........
Have you seen Ivan Miranda's GIANT DIY 3D printer? (on his channel here on YT) Something like that would be invaluable for community projects, I'm hoping to make one in a group I want to start at a charity I volunteer at in Cornwall. Your content has made me think of how we could collectively focus on projects which could help ease communities lives.
It should be same diameter so the input energy is the same. Also larger diameter means more inertia. Finally, blade angle...flatter blades go faster. More angled blades move slower with more torque.
Would they angle of the blades on that tutorial fan blade need to be straighter up and down towards the van it's designed for pushing with the angle need to be reversed for design for receiving
I bet the mass/surface area of the toroidal blade was a factor. If you could make the blades the same diameter of the original one, your findings would be different.
I would expect that at average outdoor atmospheric wind velocities (say 1 to 10kts), the shrouded box fan would turn slower, and would likely produce less wattage than the Toroidal propeller. Also, that placing both under load and measuring wattage rather than open circuit voltage would produce different results and might even stop the box fan where the propeller driven generator would still operate as it has more torque at lower wind speeds.
You're comparing apples and oranges. The diameter and weight (mass) of the 2 blades are very different - larger diameter will spin slower than small diameter for a given velocity of air; higher mass may affect top rotational speed as well. Not a good comparison.
i want to take a 12v fan push wind through a wind tunnel to increase wind speed to steadily power a wind turbine without wind fluctuations. i want to use a triboelectric generator to power the 12v fan.
@@AndreaDingbatt ok ill do that im getting the parts this week for the water powered triboelectric generator but i wont have enough for wind turbine section.
@@geninji6117 Oh My Goodness!!! Thank You, that would be Brilliant!! Water-Power is Exact;y what Im looking at!! Ive got a small piece of land, with a Riverfront, Im just getting the last of the money together for it! And,,,Please understand that I was not being sarcastic, (my Hubby tells me that my Enthusiasm might well seem that way?!) Im going to be in the Pennines, so wind-power might be useful, ~but tends to be gusts,rather that a steady, reliable source, unlike water! I honestly wish to learn(*again..)as much as possible!! (Due to a *TBI,) Grateefully Appreciate your reply Thank You! Kindest Regards and Best Wishes!! Andrea and Critters. ...XxX...
@@AndreaDingbatt im happy to share, im a ten year army infantry combat vet with two tours and TBI myself so no worries. my partner encouraged me to make a public post because id like to share these ideas ive been knocking around for awhile. the triboelectric generator im looking to make uses ptfe tubing, ito material, aluminum tape, 4v dc fish tank water pump and 2 ac to dc converter chips. with this i hope to make either a closed looped system or a fountain. that said i wouldnt recommend using anthing ptfe if youre going to introduce it back into the water environment. PTFE is a source of microplastics. from my understanding from this channel you can use alternate materials to achieve the same thing but im trying this route first with a few future remodeling of prototype designs.
@@AndreaDingbatt also my aim is to create a 12v car battery out of the triboelectric device to be plugged into something like a car inverter to power a 12v AC fan to push wind through a wind tunnel to power a wind turbine in a controlled environment. providing power 24/7 with no regular surprises you cant always predict.
You are conflating torque and speed. A better blade shape might give you higher torque but not necessarily higher speed. Generally speaking, in these arrangements, you maximise the rotation speed by having fewer blades, at the expense of torque.
The (presumably) larger mass of the toroidal will mean more wind energy needed for similar rotational speed. Also unclear whether other conditions, such as the area of the cone of air, will impact the two propellers differently. In the end, though, the task of "catching" air is not the same as pushing air as a propeller does. A basic, more or less flat and broad shape is probably going to outperform a "fancy" shape like a toroid. Perhaps a toroid which conforms better to those parameters would provide some advantage.
I love what you do. I am a 19 year old german dude and I've always loved science. What you do inspires me greatly!
love the small detail at 00:15 of catching the doctor as he is walking out of his tardis 😄
I missed that, so I'll go back in time to catch it.
I think what you should be measuring is, the minimum air speed required to turn the generator, and whether it will still turn under load. I think your fan blade will turn with less real breeze and will continue to spin under a much greater load. And if I am not mistaken, with a long shaft it would convert well to a turbulent vortex water generator. Anyway, the fan was very ideal source for the stock pc gen.
Loads of things could play into that result: Weight, number of blades, the housing.... but as a simple, cheap, easy and effective test-rig, it can't be beaten!
Thank you very much Robert!
"Keep it Simple!"!!
(KISS!!)
is a Splendid Motto ~For Myself Especially!!
These things are all over the Place and people are forever throwing them out!!
It's a Far Better thing,,,
~that we Use these,
Rather than Thow them out!!
Many Thanks again Robert!!
That was unexpected. Perhaps the housing has more of an effect than we thought.
yes, fan housing always helps increase the speed.
Of course it does. My experience with auto mechanic jobs has shown me the cause effect of the fan shrouds on radiator cooling fans. The difference of wind velocity is easily double with the shroud installed. Also with a single webber carb on each cylinder the height of the velocity stacks or tube on top sucking in air has a definitive change on engine performance
The small fan matches the size of the hairdryer so is more efficient,creating more RPM, so more voltage. For a more accurate measurement both fans need to be same size.
Another banger of a video mate! Keep up the excellent work, we appreciate you greatly.
I will suggest to have an small wind tunnel so all your tests have close to same conditions. But this is up to you and only for you (we all can make our own tests if we want to have "real" data). You have provide the spark to start our curiosity already!
I love the "old" format. Thanks Rob!! More great insights.
Appreciate the close up filming Rob.
That's brilliant Robert, keep up the good work👍👍
The airstream from the hairdryer was going right through the large holes in the LARGE toroidal propeller. I would make both propellers the same size and both in an enclosure.
Great vid Rob
the benefit of that MIT propellor isn't so much it's wind speed to rotation efficiency but rather its input wind speed to output wind speed as a motor - if you were to use these as motors and check the output wind profiles, the computer fan likely has very heavy turbulence (which is actually good for its application - heat dissipation), whereas that MIT propellor, judging by its shape, most likely maintains laminar flow (which is good for efficient propulsion)
Thanks for the video: The premise is slightly incorrect: Large diameters don't spin faster, but they do provide more "torque".
Probably to make this a fair test, you would have to scale the MIT prop down to the same diameter of the propeller fan. (Or vice versa).
One other thing, I have watched some videos on the MIT prop, and I can say so far all of them have been "underwhelming" as far as performance in "Air".
yes, hold the blower 18 inches from each generator and test again. big blade should turn better at lower wind speed
I saw that without any testing. Air turbine blades need their own design because they are removing power from the airflow, not pushing power into it.
Large diameter sweep areas always remain the same in the designs no matter how much blade area is added.
The numbers are formulas that can be changed to take more or less power from the airstream.
With geometry we can add/or remove, more or less blade area to the sweep area.
The big question for me is, "Drag?"
How can I add more push surface without increasing the drag?
Robs' blade that he has designed can easily become a lot more efficient, by changing the angle of the blades to 45deg to the post instead of 90deg while keeping the rise the same, and adding a curve to the bottom of a steeper cone. This would help in the upscaled designed.
I also see design solutions for the blades themselves that would virtually eliminate drag.
Also as we all see his blade is twice effictive if it is faced into the wind as opposed to a vertical application.
I'm a poet, not a scientist.
Take it easy on me.👁
Love the touch of Dr. Who in the use of the phone booth as a prop. :)
Robert is truly striking me more and more as a real life Dr. Who in the science corner.
He is just playing around and having fun. Trying to justify it by calling it an experiment 😊😂 Bravo!
Some good bird noises there.
🐦 That bird in the background sounds like it must be the same ones waking me up in the morning. Please make a harmless and silent repeller next 🙏🏻
Would like to see a same size comparison.. TY for your outstanding videos.
Great stuff. Thank you. I've often wondered if the contest done on the RUclips channel "Majorhardware" would work in reverse? They test to find the best fan design for moving air, quietness and things like that. I wonder how good the best ones would do at generation? Just a thought.
If you have a wall of 'hearing trumpets' all feeding into a point, the directed wind current will be amplified to a degree that you should be able to get enough air current to push something that'll generate an actually useful amount of wattage.
At the end the PC fan entire surface was taken up by the blow-dryer whereas the Toronto fan only a portion of it was taken up which is why all the energy was not grabbed by the fan thank you
the voltage is directly connected to the RPM. The MIT one has a different pitch and size, and looks to spin slower. So lower volts is to be expected. but the current output is possible higher. although i think you would get more power out of these generators with higher voltage/more rpm.
I already have a rf 455mhz remote water level indicator at high floor of the building, feed by a solar cell charging a Liion battery, but when cloudy for days I can't take the measurement, I will put one of these fans as generator to have two power sources to charge battery.. Thank you so much for you very didactic videos..
The hand holding the toroidal version is in the air flow and will therefore reduce the efficiency. That may be why the result was disappointing
There is a large area on the toroidal fan where the air just bypasses the blades. Perhaps a more complex shape where the loops are interlaced would improve the result. Interlacing could allow for more blades while retaining similar angles to the direction of airflow. An example of the interlacing I envision is the turks head knot although more blades would be an improvement along with the interlacing.
I want to add in as many toroidal blades as possible! Great ideas keep em coming
The primary benefit of the toroidal propeller is its low noise generation. You could say their are trade-offs between size, power output, efficiency, sound generation, and complexity. As has been addressed in a previous video "the best design is not always the most efficient." I could see the low sound generation being preferred in areas where you want to keep noise pollution at a minimum.
The hair dryer has a small circle of concentrated air flow, about the size of the small fan. You had it pointed to one corner of the bigger fan. The big one did not come near to experiencing or capturing equal energy. Try 3 time that distance pointed at the center of both.
Perhaps try one inside the box the other was in or have outside bearings where it wants to vortex thru the center
Try purifying dirty water with it....I think it's a thing! Great video as always..Thanks man!
The unloaded rpm of a blade will in part be a function of the pitch of blade rather than the diameter or swept area. 😊
With very low voltages on each of two coils 90 degrees out of phase, It might help to have a voltage doubler circuit. (Two diode two capacitor) for each coil. Then one can put the outputs of each doubler in parallel with the other. Under light loads it will virtually double the peek voltage (sqrt(2)× rms) of a single coil minus voltage drop of diode.
I'm sure the housing had some kind of effect but the train of thought that's being exercised here is the point and looking forward to future tests :)
At the distances shown, the hairdryer is directing air over only a part of the toroidal propeller's swept space.
My suspicion here is that toroidal prop would benefit from real wind scenario instead of the overly small wind profile the dryer offers.
The dryer is, I suspect only capturing a smaller volume of that overly focused air stream but against a widened stream (say a large diameter fan) would perform very differently.
Just my supposition but it’d be nice to find out
Your hand behind the Toroidal Propeller could be causing a wind resistance and combined with the hair dryer's angle is about 20degrees off center could also cause a reduction in output, but not that much. Back to the drawing board. Another GREAT VIDEO!
If I were 60 plus yrs younger and you'd been my science teacher.
I might have become an Ienstein or at least a physicist...
what I am wondering is if you could just solder some wires to the points of output with out altering anything else and still be able to use it as a fan or generator based on which wires you are hooked up to, and possibly even hook the generator output wires to a reader so it would let you know when it is running by counting the pulses coming from the generator output the way they do with some stepper motor drivers that use the back EMF that comes from the unpowered coils when the motor moves to know a step in the direction was accomplished (ie it reads the motion) and if this back EMF does not occur it warns the software that the machine has not moved, turning the idea of an open loop CNC system into a complete closed loop system (each step sent waits for a reply to let it know the motion has been moved before it shuts off and sends the next pulse for another step, counting according to the software to reach it's destination, otherwise it will assume a step has been lost, where the machine being bound up causing a lost step in an open loop system will have no idea this has occurred and thus the machine will not know where the cutter (or extruder for 3D printers) is actually at. )
The test result is pretty much expected. The original traditional fan blade have more surface area and density (surface area of blades per area of 12 cm fan) for the air to push. Thus, it generates more voltage.
There is a lot of eyeball visible axial runout as the toroidal fan rotates and possibly some radial that's not as visible. This will rob a lot of the potential power generation potential. A bit more precision at the axle to fan joint might yield some performance benefits.
Could you do a video on using solar panels directly with peltier to make an air conditioner or cooling blanket?
Loved the not so veiled reference to Dr Who
I think the blade pitch on the toroidal fan isn't steep enough so it was rotating a lot slower than the PC fan.
Hello old chap- I’ve been watching your rather excellent instructorials and I’ve been wondering… would you be interested in doing some on ways to mitigate or counter certain applications’ planned obsolescence?
Wonder if the airflow from the hairdryer is concentrated on one spot, coincidentally the same size as the pc fan - a wider 'tunnel' of air may show different results - enjoyed the video
The torpidal fan was not fully 'illuminated' by the 'wind', whereas the pc fan was pretty much fully engaged..you needed to test at a greater distance from the hair dryer, to get a larger, more consistent air flow, this would have the pc fan experience much less wind energy, amd the toroidal would be more completely driven. As others have commented, there is also the question of deliverable power, since your test is open circuit...consider how aircraft propellors use different pitch to deliver takeoff power with low airspeed, and higher pitch for power delivery at higher airspeed...
I'm going to freeze sand in our freezer this summer and make myself an aircon. To hell with it. greetings from south africa
Empathy from a melting woman in the UK!!❤
Mr. Robert Murray-Smith
I would be curios to see the same experiment again but instead of measuring the open circuit voltage measure the short circuit amperage.
I wonder if the longer blades on the toroidal propeller are providing excess leveraged mass reducing top RPM and limiting OC voltage but perhaps increasing SC amperage leading to turbines of similar wattage but a preference for higher or lower speed winds.
What do you think?
Regards,
Borel's Monkey #4
Your channel reminds me of the TV program from the 90s called Beyond 2000
That's amazing !!
Imagine it inside a Darwin Tower!
You mention a front and a back with the toroidal fan. I have been wondering if they would work underwater as a generator using tidal currents. The Severn has the second highest tidal range in the UK. Thats a lot of water going in and out. So instead of using barrages to store and release water, what about installing something sub surface to capture the energy in that movement? So is there a front and a back? We need a fan/prpellor that works efficiently in both directions. Just a thought.
Is that the same design that they are. Claiming makes for a more efficient marine propeller?. Perhaps the reason it works as a marine propeller is because it's being used for thrust in a denser environment. Perhaps you could do a comparative experiment on this please
What about a big blade hooked up to gears to spin the 'fans' (generators) with 'fan removed' ?
I don't think there's any mathematical equation to back up this... but... it would seem like the toroidal propeller has a lot of empty space between the fins whereas the computer fan blades do not. I think for air movement, the pitch of the toroidal propellers needs to be rotated about 90° and needs a helluva lot more fins. More plastic covering the open space and an easier angle for the wind to blow past it... With the pitch being nearly perpendicular to the axis of rotation, that would be really good for moving a slower, heavier (meaning has a lot of mass) fluid rather than a faster, lighter fluid like air or any other kind of gaseous substance. I think you need something a bit more parallel to the axis of rotation.
What are you working on in your photo Rob? Great video.
Very neat stuff Robert. Is it possible to make a Homopolar motor in to a generator?
Possibly the larger diameter of the fan means it can't spin as fast as the smaller one. It may produce a higher torque which needs gearing to get the same revs.
You soldering iron looked much like an old - WEN- 'QUICK HOT' Unit I recently salvaged. The internal design is far more robust in its construction than my recent smoked, made in China iron. I have such high hopes for thi device, but I can't manage to fond or create a tip that will get hot enough. I am determined to revive it, and it seems S though I could run some cables up to a hand held tip rather than having the other kilogram of weight in my hand.
Any suggestions would be greatly appreciated. Thanks
Iv recently wondered how much energy you could get from one of those hand warmers. Those ones that have a stick of smouldering charcoal in and that can keep warm for hours. A few peltier jobbies slapped around the outside of that with possibly a water cooling system as a differential engine might work as a small portable generator that doesn't need refueling or stoking every 5 seconds. Maybe with an option to increase airflow with vents should you need an extra boost of heat/voltage at the cost of less fuel efficiency
May be other blades gives more torque but at lower speed?
Can you do videos on zero-point energy?
Do the generator need to be directly fixed to the fan, or could it be placed at the end of a gearmechanism to maximize spin?
Nice phone box Tardis…..is that how you get about for these outside broadcasts?
Is that a phone booth behind you. I don't believe my eyes. You are very fortunate
🤔
Maybe printing the toroidal blade with a ring around it, magnets on the outside of the ring, and the serpentine coil from a previous video?
IDK, this video has me stumped. I thought the t blade would have done better, but does it have something to do with RPM vs Torque?
I'm so lost on this one 😂😂😂
If the toroidal blade produces more wind,
and the standard blade catches more wind,
what is the difference in output from wind
generated by each blade and caught by the
same generator?
Hey, I just spent the past week setting up a
Linux server, I had to ask a silly question to
destress.
At that range the stream of air from the hair drier is focused only on part of the toroidal propeller, and the rest will be using torque to drive more air, thus wasting energy.
Hmm - with these comparisons - needs a variable load (dynamometer) to determine peak power output in a given air stream....
Free stream speed is a fairly low quality prognosticator... (blade pitch governs unloaded rotational speed).
First great stuff.
Second. I work for a company that sends out replacement pc fans but none with a usb plug. We have redundant ones every now and then.
How to replace the standard (flat) pc plug, Please.
Can it go wrong?
I know that you can't user a propellor as a windmill because the 'top' of the airfoil is on the wrong side.
Well, you can use them, but they will be ridiculously inefficient.
Surely the same principle applies to any propellor/windmill swap?
The outer regions of the toroidal blade is mainly focused for silence, but seemingly not so much for optional conversation of air does to rotation speed. If it was so efficient, we might have seen that design in turning engines already..? With a probably designed static guide blades, a gas turbine can reach efficiencies well above 90%, so that's really hard to beat, probably.
The tips of the blades help a lot to reach maximum speed, so the silent trade-off clearly seems to cause a significant reduction in efficiency...?
"air does" = "air speed". Swype error, but it won't let me edit on my phone..
I think your air flow has about 100% coverage of the frontal area of the pc fan, but probably less than 30% coverage of the frontal area of the much larger toroidal.
But you'd still expect the results to be more similar, given there's a similar amount of air moving through both.
I suspect the toroidal doesn't work very well unless it has air pressure across it's entire surface perhaps?
There's an interesting YT channel which tests novel 3D printed designs for pc fans. Toroidals don't actually stand out in those tests. Also, the cowling shapes very much matter.
I would be happy if a 20" box fan tolaroidal replacement blade went on sale not necessarily to be more efficient just add a little more wind to the situation for funsies
They are hall effect sensors
Is it possible to use drone motors to generate?
The rotational inertia of a bigger blade causes it to spin with less RPM. Basics physics ;) try making one with same diameter, but less mass
Robert, it lookes like you issed a lot of the tiroidal fan with the smaller dimatior of the hair drier output. Try this again with a drive fan that is larger than the fans under test, you will not miss so much of the fan you are trying to drive.
aLex..........
Have you seen Ivan Miranda's GIANT DIY 3D printer?
(on his channel here on YT)
Something like that would be invaluable for community projects, I'm hoping to make one in a group I want to start at a charity I volunteer at in Cornwall.
Your content has made me think of how we could collectively focus on projects which could help ease communities lives.
It should be same diameter so the input energy is the same. Also larger diameter means more inertia. Finally, blade angle...flatter blades go faster. More angled blades move slower with more torque.
❤️✌️
Maybe your hand behind the toroidal propeller is blocking the airflow.
Would they angle of the blades on that tutorial fan blade need to be straighter up and down towards the van it's designed for pushing with the angle need to be reversed for design for receiving
Maybe a turbine prop manufacturer would do something with this design(if their not already)
The noise reduction would be great for wind turbines, one of the main complaints I hear is the noise really
I bet the mass/surface area of the toroidal blade was a factor. If you could make the blades the same diameter of the original one, your findings would be different.
TESLA,TESLA,TESLA!!! LET'S C IT!!!
Perhaps if the latter fan were ducted like the original, it might improve its performance.
some thing to try, turn the generator into a bedini motor/generator
Please reach out to Douglas Vogt of the Diehold Foundation. Thank you sir.
Then there’s the new Zip propeller.. 😊
Many propellers in high pipe, 100m aeromine
I would expect that at average outdoor atmospheric wind velocities (say 1 to 10kts), the shrouded box fan would turn slower, and would likely produce less wattage than the Toroidal propeller. Also, that placing both under load and measuring wattage rather than open circuit voltage would produce different results and might even stop the box fan where the propeller driven generator would still operate as it has more torque at lower wind speeds.
You're comparing apples and oranges. The diameter and weight (mass) of the 2 blades are very different - larger diameter will spin slower than small diameter for a given velocity of air; higher mass may affect top rotational speed as well. Not a good comparison.
Now put a load on it, and you will find that the larger one produces more power.
i want to take a 12v fan push wind through a wind tunnel to increase wind speed to steadily power a wind turbine without wind fluctuations. i want to use a triboelectric generator to power the 12v fan.
When you have that set up can you plz post a video about it?!!
Thank you and have a wonderful weekend!!, ❤
@@AndreaDingbatt ok ill do that im getting the parts this week for the water powered triboelectric generator but i wont have enough for wind turbine section.
@@geninji6117 Oh My Goodness!!!
Thank You, that would be Brilliant!!
Water-Power is Exact;y what Im looking at!!
Ive got a small piece of land, with a Riverfront, Im just getting the last of the money together for it!
And,,,Please understand that I was not being sarcastic,
(my Hubby tells me that my Enthusiasm might well seem that way?!)
Im going to be in the Pennines, so wind-power might be useful,
~but tends to be gusts,rather that a steady, reliable source, unlike water!
I honestly wish to learn(*again..)as much as possible!! (Due to a *TBI,)
Grateefully Appreciate your reply
Thank You!
Kindest Regards and Best Wishes!!
Andrea and Critters. ...XxX...
@@AndreaDingbatt im happy to share, im a ten year army infantry combat vet with two tours and TBI myself so no worries. my partner encouraged me to make a public post because id like to share these ideas ive been knocking around for awhile. the triboelectric generator im looking to make uses ptfe tubing, ito material, aluminum tape, 4v dc fish tank water pump and 2 ac to dc converter chips. with this i hope to make either a closed looped system or a fountain. that said i wouldnt recommend using anthing ptfe if youre going to introduce it back into the water environment. PTFE is a source of microplastics. from my understanding from this channel you can use alternate materials to achieve the same thing but im trying this route first with a few future remodeling of prototype designs.
@@AndreaDingbatt also my aim is to create a 12v car battery out of the triboelectric device to be plugged into something like a car inverter to power a 12v AC fan to push wind through a wind tunnel to power a wind turbine in a controlled environment. providing power 24/7 with no regular surprises you cant always predict.
You are conflating torque and speed. A better blade shape might give you higher torque but not necessarily higher speed. Generally speaking, in these arrangements, you maximise the rotation speed by having fewer blades, at the expense of torque.
The (presumably) larger mass of the toroidal will mean more wind energy needed for similar rotational speed. Also unclear whether other conditions, such as the area of the cone of air, will impact the two propellers differently.
In the end, though, the task of "catching" air is not the same as pushing air as a propeller does. A basic, more or less flat and broad shape is probably going to outperform a "fancy" shape like a toroid. Perhaps a toroid which conforms better to those parameters would provide some advantage.