Magnus effect vertical axis wind turbine, No blade, start quickly 

Currently, lift-type vertical axis wind turbines are started at the expense of reduced efficiency or increased complexity(cost).

thanks

Thank you for watching and agreeing

Have you ever seen what happens when a turbine is overdriven due to excessive winds? Speed control could be of use in such conditions.

The efficiency of the Magnus effect is not low, but humans have not found a reasonable way to use it. In addition, it doesn't matter whether there are protusions or not.

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@@SmartServo_org have you tested protrusion depth and/or angles to see efficiency data at various speeds? Hook up to a generator?

If it works _off of_ smooth cylinders, then what does it work based *ON?*

At 0:59, he is holding a part called a slip ring. It’s like a bearing, but allows electrical wiring to go through and spin with the bearing using brushes like a motor. A lot of thing that spin and use power use them. Like an amusement park ride that has lights on a spinning part.

Since no windflow in the room, he simulates it with help of electric fan. Different case if he runs it outside

@@gargantuationex1120 i understand that, but each tube has a gear motor attached to it. It looks like the tubes are driven, not blown

The motor drives the rotor, and the rotation of the rotor causes the wind to generate torque (Magnus effect) to drive the main shaft. The rotor acts as a catalyst. Although it has not been proven that the energy output can be greater than the input, it is possible => smartservo.org/en/magnus-vawt-implement-en/ This video(ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html)@1:31 shows a larger one running in a wind tunnel.

2 words, turbine engine. Which uses the airflow it compressed and ignited to drive the compressor section. Just correcting your turbine definition. A turbine can harvest power from a gas or a liquid. You're welcome.

Yes, experiments are necessary

thanks a lot

Thank you for your advice and encouragement, which made me feel warm. I have made a bigger one of this type., which is only shown briefly @1:30 of this video => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html . and I found that there are several ways to improve the efficiency: (1)Reduce the inertia of the rotor. (2)Recycle the energy when the motor decelerates and supply it to the accelerating motor, (3) Increasing the lift-to -drag ratio of the rotor, I believe that when these are improved, at sufficient wind speeds this wind turbine can be used to generate electricity.

Two thumbs up, and full speed ahead, Jehovah bless.😊

thanks !

Thanks for your appreciation.

thanks

Thanks for your comment, I think we are using very different approaches, but good luck anyway.

No, I wasn't the first to think of this method, it's just that people in the past didn't have the help of modern technology (MCU, motor & drivers) to make it easy to implement. The new idea I came up with is => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

thanks

Thank you for your comments, also inspires me, I think RU-vid is a good platform to show your work and communicate with people all over the world. If you have a good idea, don't bury it.

The rotors of Challenergy's wind turbines still have to spin, they just don't have to change direction. Don't you think it's strange that the upwind and downwind torques don't cancel out? Is there such a perfect way in the world? Or is something sacrificed so that the rotors don't have to change direction? The real way to keep the rotor from spinning is to make good use of this much-criticized device =>(see ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html),@ 4:03 when the rotation speed is fast enough, the rotors can be stopped and no more energy is consumed.Therefore, I don't have to rush to prove its efficiency.

Thanks

Although the (Darrieus) turbine using blades is highly efficient, it is difficult to self-start. When combined with this device, it can take into account both efficiency and start-up. => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

Thanks🙂

thanks

thanks

When the size of the wind turbine is enlarged, the rotation speed will also decrease. Therefore, the frequency of changing the direction of the rotor is also reduced. The method of improving efficiency can refer to => smartservo.org/en/magnus-vawt-implement-en/ ,before success, To start the Darrieus turbine is a reasonable work(see ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html), when the rotation speed is fast enough, the motor can be stopped(@ 4:03) and no more energy is consumed.

If you are interested, you can read this patent (US4446379) to know how people in the past solved this problem mechanically. Fortunately, there are more technologies available in this era. By the way, your method is also very clever.

No batteries, no wireless, all power lines of motors are connected via a slip ring under the main shaft. see video 0:59

thanks, I will

When the radius of the turbine becomes larger, the rotational speed decreases naturally and the rotor does not have to change direction frequently. The blades that changes orientation are what's called "active pitch control",which may be too complicated for ordinary people to implement. The pitch is also driven by a motor, which is difficult to drive directly due to the weight of the blades. Therefore, the transmission mechanism and gearbox should be unavoidable and easily lead to failure. However, the Magnus rotor can achieve required lift by increasing the rotation speed, unlike the blade that needs to increase the surface area, so the rotor is lighter and easier to integrate with the motor to achieve direct drive, making the structure more reliable. In addition,for active pitch control, the chord must be constantly changing with the relative wind direction to maintain the correct angle of attack(AOA), which requires a closed-loop servo system to precisely control the position, which is more complicated. On the contrary, using Magnus rotor only needs to do open-loop speed control, controlling the rotor’s position is not necessary, which is much simpler.

The phase of the rotor is not determined by the mechanism, but set by software. The encoder under the main shaft can detect the position of the rotor, and with the anemometer(Not necessary for wind tunnels), the angle between the wind and the rotor can be calculated. The software then add an offset to each rotor.

@@SmartServo_org phase angle detection is via the underside . you need to account for apparent wind .

the cylinders are driven by motors to produce the spin on the main shaft so diminishing returns i'm afraid.

@@GoldenAdhesive My idea would use the mechanical input of wind to turn a brushless motor for electrostatic output. It would not experience a reduction of "power," because technically electrostatic charge isn't a thermal effect. It can create heat in the form of voltage/electricity when inducted with a transformer though, and that's what I'm suggesting.

@@GoldenAdhesive I think he just used the electric fan to simulate wind. If his cylinders are actually very sensitive to wind, then they'd be great for generating their own charges that could be combined in the central vertical shaft/housing via a transformer.

@@davidt1621 check out his other videos he has intentionally mounted small motors to the bottom of the cylinders to turn them in opposing directions when required. He also provides a valid application for it.

@@GoldenAdhesive That's cheating though. The magnus effect is powered mechanically from natural airflow.

In my project I used PLA as my 3D printing material, but after about 1 year it has been bent due to the weight of the motor. Maybe ABS with better mechanical strength is more suitable for this, but still not suitable for large models, and ABS requires more 3D printing skills. The electronic components I use are Arduino UNO controller board, L298 DC motor driver board x3 and optocoupler modules x3.

@@SmartServo_org Thank you and all the best!

The reason traditional lift-type VAWTs worry about changes in wind speed is that the angle of attack(related to TSR) will be affected and possibly cause a stall. Magnus rotor is immune to wind speed changes, because the circular rotor has no chord, so there is no angle of attack, and no stall problem.

If you're talking about turbines made by a Japanese company (Challenergy), there's something different. They added a plate behind the rotor to shield the Magnus force downwind so that the motor didn't have to reverse, but it also lost some lift. What this video shows is the original untouched concept of Magnus VAWT. Although there are many problems, it could trigger some imagination => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

The Darrieus type is the most efficient vertical axis wind turbine, but it was not used successfully due to many unsolved problems such as poor starting ability ,dynamic stall and overspeed in high winds, while the Magnus type is easier. Therefore, if the energy consumption of the rotor can be minimized and the efficiency of the Magnus-type turbine can be improved, this may be a good VAWT solution (more info=> smartservo.org/en/magnus-vawt-implement-en/), in addition, the Magnus rotor can also help Darrieus turbine to start easily.=>ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

Thanks for your suggestion, I will consider it.

The Magnus effect on the rotating cylinders is making them travel upwind.

@@alanhat5252 I’m sorry but my brain must be smaller then I expected . I STILL DO NOT GET IT lol

There are 4 axes: The 3 cylinders and the big axle in the middle. The generator is the big axle having the wind rotate the whole thing, but for that the individual cylinders have to rotate around their axis and that's what the 3 motors are for.

@@DiThi thanks for that. I get it now! 👏🏽👏🏽

The fan is to simulate the natural wind that might power such a device.

except magnetic/airfoil bearing

The acceleration and deceleration of the rotor will not cause bearing damage, it is caused by stress. Moreover, when the size of the wind turbine becomes larger, the rotation speed can be reduced, and the frequency of acceleration and deceleration is naturally reduced.

Exactly, and it takes a ridiculous amount of power to reverse direction TWICE every revolution.

While Magnus rotors have had some problems with vertical wind turbines, all other approaches have not been successful, otherwise they should be everywhere like HAWT.

Fusion 360

More like Steely Dan cover band jam session

What's the point?

Thanks for your comment, let me explain your doubts： 1, Although it takes energy to rotate the cylinder, there are still ways to minimize energy consumption, see => smartservo.org/en/magnus-vawt-implement-en/ And don't forget that wind energy is proportional to the cube of wind speed. When the wind is strong enough, a net energy is produced. 2, The mechanism was chosen for this project simply because it was cheap. A set of DC motors and gearboxes cost less than $2 USD. Direct drive is also possible to eliminate the need for a gearbox to reduce complexity. => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-XmZwYpoKQ8Y.htmlsi=CRQ2mNfxw8CiiLoG&t=97 3, Due to the advancement of new motor technology, brushless motors are widely used in drones and remote control aircraft, which are reliable and cheap and suitable for our use.

It's just a conceptual model and it's too small.

It likely produces much less energy than it takes to run. The arduino is powering the rotation of the cylinders, which also requires even more energy to reverse the cylinder rotation half way through the rotation of the whole turbine. It's nifty demonstration of the Magnus effect, but isn't a generator by any means because it is constantly working against itself with reversing the rotation of the cylinders, plus the significant extra friction from all the bearings. The magnus effect is a very light force compared to just the direct force of the wind captured by a blade passively in a traditional turbine. So it's putting in more energy to rotate the cylinders for less rotational energy captured by the wind. Easiest way to think of it, for as fast as the demonstration was rotating, putting a similar scale blade turbine in front of that fan would be spinning much faster passively.

The motor drives the rotor, and the rotation of the rotor induces the wind to generate torque(by Magnus effect) to drive the main shaft. If the fan is not turned on, the main shaft cannot rotate.

@@SmartServo_org I'm aware of how the Magnus effect works, I'm just suggesting that maybe not all of the initial speed is caused by the Magnus effect alone.

This is an interesting thought. I made an odd sculpture where angular momentum was transferred to different parts just by the overall rotation of the whole. I wasn’t expecting it, but it was quite cool. Certainly the angular momentum of the rotors has to go somewhere when they reverse.

@@danajohnson5993 Because each rotor rotates at a different speed and direction, for example, when one rotor is accelerating, the other rotors are decelerating, and the changes in angular momentum may cancel out.

@@josephgauthier5018 In the future, I will add a video of the rotor turning before the fan is turned on.

This project only uses the PWM of the arduino UNO to control the L298 DC motor driver. It is programmed in C language.

Here are ways to reduce power consumption and improve efficiency => smartservo.org/en/magnus-vawt-implement-en/

Yes, this is a necessary step for testing the turbine outdoors. Before that, I needed to redesign the structure to make it bigger and stronger.

Simply using a fan is different from a wind tunnel, and there will be no wind tunnel effect. Also, the Magnus effect works both in the wind tunnel and outdoors, just like Messi can kick a banana ball without being in a wind tunnel.

The Darrieus wind turbine does have the problem of overspeeding when encountering strong winds, and it has not been effectively solved. Therefore, some designs use multiple blades (large solidity) to reduce the speed, but it also leads to low efficiency. not a good idea. The work of the VAWT has not been completed yet ...

The two Pac Wind VAWTs in my neighborhood blew apart in the same storm 10 years ago. One was the real big model and it just blew apart. The guy spent a fortune on it even the pole in the ground was really expensive because it was so big and so thick and had such a large concrete base.

Of course, this video( ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html ) shows a second version using BLDC motors. It is used to start the Darrieus turbine, when the rotation speed is fast enough, the motor can be stopped(@ 4:03) and no more energy is consumed.

Thanks for your opinion. The motor drives the rotor, and the rotation of the rotor causes the wind to generate torque (Magnus effect) to drive the main shaft. The rotor acts as a catalyst. The energy consumption of driving the rotor is not large. It only needs to overcome the viscosity of the fluid , the friction of the bearing and motor, which is less than directly driving the whole turbine. Although it has not been proven that the energy output can be greater than the input, i think it is possible => smartservo.org/en/magnus-vawt-implement-en/

Study mechanical engineering, work as a firmware engineer, not related to wind energy

Thanks for your comment, I made a bigger one with slim rotors to reduce inertia and drag, if you are interested you can refer to the video @ 1:31 =>ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

Although the two are similar in appearance, they have different uses. The Magnus device is used to generate power in a flowing fluid.

@@SmartServo_orgthank you for your fast response, i dont know if i got you right, but shouldn't it be possible to use a voith Schneider Propeller to generate energy from a flowing fluid as well? Woul be like a darrieus Rotor with a flexible pitch. I Think that the cylinders have a higher resistance than wings, but i ask myself if the higher lift could Balance that..

@@f.u.52 Darrieus wind turbines have high efficiency with or without active pitch control. High efficiency can be achieved by using high lift-to-drag ratio blades and operating above TSR 4. However, the rotor has a low lift-drag ratio and is therefore not suitable for operation at high TSR (Tip speed ratio). I think using high aspect ratio rotors with number >= 4 and running at TSR 1~2 should achieve good efficiency.

Yes, the motors are required to drive the rotors when starting, but not when stopping.

For this device to be meaningful, it must first solve the problem of energy consumption. Before that, combining it with lift blades may be a way to create value in the short term. Please refer to =>ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

@@SmartServo_org why does it need energy? Do you really have to spin the columns manually ? Wouldn't just using the column spin to generate energy work? use the back-EMF to control the rotation, you would only need energy to start it. Nevertheless nice idea, but too many moving parts.

Fusion 360 =>www.autodesk.com/products/fusion-360/personal

Maybe you're talking about a turbine made by a Japanese company (Challenergy), still a little different. They added a plate behind the rotor to mask the Magnus force on the leeward side so the motor didn't have to reverse, but it also lost some lift. This video shows the Magnus VAWT in its original concept.

The rollers aren’t reversing direction, and @4:30 he did use an anemometer

The method of improving the efficiency can refer to => smartservo.org/en/magnus-vawt-implement-en/

Thanks for the comment. The Magnus effect can be used to propel a boat, but maybe not for a car, because the car needs to change direction from time to time, but the wind direction may not be appropriate, or even no wind.

When the radius of the windmill increases, the rotational speed naturally decreases. Because the linear velocity is constant.

@@SmartServo_org I must have missed something. I do see in your other vid and I understand that the rotation changes direction when between leeward and windward . But how fast can that be done? (I know it may also depend on the moment of inertia of the rotor. E.g. would they be built out of lead, I cant see how a small motor could do the direction changes.) Nevertheless, your project is very inspiring, so keep up the good experimentation.

The energy consumption of driving the rotor to generate Magnus lift is not large. It only needs to overcome the viscosity of the fluid and the friction force of the bearing, which is lower than the energy consumption of directly driving the whole windmill because the wind energy is used. The method of improving the efficiency can refer to => smartservo.org/en/magnus-vawt-implement-en/

Without wind it cannot start spinning relying on the Magnus effect. If it is already in motion it will have the Magnus effect but I think the force will be directed inwards or outwards without contributing to the rotation

You can see the Norsepower.com =>www.norsepower.com/key-advantages ,can typically produce 5-20% fuel savings.

Adjusting the potentiometer is to control the speed of the main shaft, which is beneficial to keep the turbine at the rated speed under strong wind to avoid damage.

Portable wind turbines also have market potential and are in demand by travelers or campers.

I think cylindrical rotors are easier to manufacture than normal blades with curved surfaces. If the rotor is made soft and hollow, it will naturally form a cylindrical shape as long as it is inflated.

It's a controlled test environment.

A motor drives a rotor, and the rotation of the rotor induces the wind power to generate torque to drive a generator. The rotor acts as a catalyst. Although it has not been proven that the energy output can be greater than the input, it is not impossible => smartservo.org/en/magnus-vawt-implement-en/

@@SmartServo_orgHence my question. But havent the setup been put through a power meter, for example?

Ermmm...A fake volcano for a science project using baking soda and vinegar. What's the point, why don't you use real lava? It's a tabletop demonstration to explain the physics behind wind energy.

Exactly what I was thinking

This experimental device is too small to generate electricity, but it can be used like this => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

You are right, but even Darrieus wind turbines have no moving parts other than the main shaft and have not been used successfully. Sometimes compromises must be made in exchange for benefits. Rotational motion is not all detrimental unless there are (1) heavy loads (2) gearboxes (3) cantilevered construction, which are not present in the project of this video when using direct drive.

@@SmartServo_org yes but now ur sounding like Nissan let’s use cvts. . it didn’t work for them

"Less" is used for amounts, e.g kilograms, litres, gallons, pounds. "Moving parts" is a number e.g. 3,4, a dozen moving parts. Hence, *"The fewer moving parts, the better"....because correct English makes you sound more educated & adds credibility to your statements.

@@topspeed250k5 ok and your point is I’m not writing a dissertation sir or mam, I can care less what u or the rest of the 8 billion on this planet think. Nobody listens to me anyways, education doesn’t mean your smart people like Tesla and Einstein will confirm that. It’s having vision. So what I said was right you made it into a cluster duck

To start the Darrieus turbine is a reasonable application(see ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html), when the rotation speed is fast enough, the motor can be stopped(@ 4:03) and no more energy is consumed. and the vertical axis wind turbine has low noise.

@@SmartServo_org soemone is distributing such a turbine for urban use ? I mean small for private homes lets say 300 or 600 Watt max

@@rainerlubke3766 Not yet, it's just a conceptual model.

@@SmartServo_org so ....

the strip on the cylinder is not necessary => ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-XmZwYpoKQ8Y.htmlsi=R0IujWvqjNI3tsB0&t=22

the strip on the cylinder presents the force for cylinder's rotation, then causes outer turbine rotating. you can compare the rotation speed difference between with and without the strips. and you can test by using the cylinder with very smooth surface such as thin foil

When the document is ready it will be posted on the website => smartservo.org/en/magnus-effect-vawt-main-en/

@@SmartServo_org thank you so much

@@CrjaseMechaEngr sorry for the late reply. Project file link => smartservo.org/en/magnus-vawt-files-open-en/

It depends on what the rated voltage of the motor you choose is.

There is a Japanese company that is working onmaking full scale versions of these. The big selling point is they can work even in violent storm winds, such as hurricanes and typhoons

@@alantupper4106 The wind turbine in this video is still different from that of the Japanese company you mentioned (it should be Challenergy). It installs a flat plate behind each rotor to cover the wind from the leeward side, so that the rotor only needs to maintain the same speed without changing direction.Although easier to control, it uses only half of the Magnus lift.

@@SmartServo_org But if you constantly change the direction of the leeward-side-rotor, you get a problem with exotic materials, that would be needed, since in such a case, the rotors have to have marginal rotational inertia, in order to speed-up and slow-down constantly. I think the japanese approach is better. Use only the half the magnus-effect, but avoid using high-tech-material-rotors (rotors made out of materials that don´t even exist yet). I thought it´s crazy when I saw it, and I thought, that if there were a way to avoid the change-of-direction, it then would be a great idea, and now you tell me that this already exists, in Japan. Build your rotors hollow, with stable spokes/beams leading to the rotors´s shell.

@@klausbrinck2137 Is it a good idea to sacrifice half of the Magnus effect for the motor not to have to change direction? Seems too optimistic until knowing how efficient it is.In addition, motors that rotate in one direction are not as good as motors that do not need to rotate.It's not too late to judge after seeing this idea=> ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html

i assume its meant to generate rotational energy for ships or as they said, VAWTs (Vertical Axis Wind Turbines) but i doubt that the amount of energy harnessed is more than it takes to drive the drums, or is less than a normal Magnus turbine or HAWT.

The original purpose of this windmill is to generate electricity. Obviously, the problem it must overcome is that the energy generated must be greater than the energy consumed. The main solutions are: 1, increase the efficiency of the rotor, >>Increase aspect ratio (slim and long) to improve lift-drag ratio. 2, reduce the energy consumption of the motor >> reduce the mass of the rotor to make the inertia lighter >>Recycle the energy when the motor decelerates and reuse it With these improvements, I believe that net energy output can be achieved above a certain wind speed.

@@SmartServo_org And when you use more than 3 of these "white thingies" ( do not know the english term) ? Do you get more rpms? And/or with longer ones?

@@SmartServo_org Wonder if you could put a small generator on each magnus-effect tube as well as a big on the main rotor?

@@stanlibuda5786 Using a longer rotor can increase the lift-to-drag ratio, which is beneficial for increasing speed.

URLs to all project files are listed below the video description. The motor model is DC130

@@SmartServo_org Hello again ! We've been going through the documents filed under the video but we still have some questions left. How did you build the gear reducer (or did you buy it ? what type is it ?) ? How does the tachometer work exactly ? And what is the purpose of the Arduino card, does it only receive information or also control the motors ?

@@EliseVeyrat you can get the gear box on amazon by searching"gear box arduino",To avoid too large a gear ratio to reduce the speed, 20 is a good choice. Since the rotor should rotate in opposite directions on the windward and leeward sides, the Arduino controls the speed and direction of the 3 motors according the azimuth sensor below the main shaft.As can be seen, two semi-circular plates are arranged at 90 degrees apart to divide a plane into 4 quadrants. at power up ,guessing at the center of the quadrant make the error less than +/- 45 degree which is small enough to drive the rotor in the right direction. when the main shaft rotates through the quadrants, the correct azimuth can be found. then count the pulse from the third plate with 40 holes on it to get the real time precise azimuth.

Maybe you're talking about a turbine made by a Japanese company (Challenergy), still quite different. They added a plate behind the rotor to mask the Magnus force on the leeward side so the motor didn't have to reverse, but it also lost some lift. This video shows the Magnus VAWT in its original concept, which predates the Japanese one.

Using DC motor driver board (L298), all project parts are listed here => smartservo.org/en/magnus-vawt-files-open-en/

​@@SmartServo_org Thanks. I think, overcoming inertia when reversing the direction of rotation of the cylinders must bring down the efficiency of this device severely.

@@minduton Yes, but energy consumption can be minimized through the methods described here => smartservo.org/en/magnus-vawt-implement-en/#improve_ways

@@SmartServo_org At this would be better to apply the "pendulum principle". Take such a pendulum at an ancient clock. It is a machine that performs a regular opposite movements, but with an absolute minimum of energy. So, install a spring or a piece of rubber coil into the Flettner cylinder, which mostly uses the energy to rotate the cylinder in the opposite direction. It is also a question whether it would not be an advantage to reduce the number of Flettner cylinders to an even number. This would make it possible to mechanically link the drive of the opposite cylinders and then maybe figure out some mechanically elegant way to use the already unnecessary kinetic energy of the opposite cylinder to reverse the rotation. This type of turbine simply stands and falls on how efficiently it is possible to recover the kinetic energy of those cylinders during their commutation. So far you are at "minus 100%" currently. :) Unfortunately. So in terms of overall efficiency, it sucks. The speed and direction of rotation of the cylinders should copy an ideal sinusoidal curve when projected onto the graph, logically. With such a course of rotation speed, the maximum efficiency of this device will be.

The materials are not expensive, mainly include Arduino UNO(10 USD), L298 DC motor Driver(2.5 USD) x3, motor & Gear box(2 USD) x3, Slip ring(10 USD), optocoupler module(2 USD) )x3, the most expensive part is three acrylic circular plates (made to order) which cost about 40 USD

What is an STL file?

Don't worry about motors, they are also present in popular horizontal wind turbines for pitch control. What important is that the energy harvested from the air is greater than the energy consumed, even if this device is questionable, it is still possible => smartservo.org/en/magnus-vawt-implement-en/

The torque characteristics of common VAWTs with blades are quite different from those with rotors, so previous experience cannot be applied here.

@@SmartServo_org what does that have to do with it, vertical turbans have only one or two and they fail...you need at least 8 taper bearings...

I believe their point was that there may be less loading on the bearings, leading to increased lifespan...

way way less, lots of energy loss. too much for perpetuum mobile

Not yet, but since the wind energy increases with the third power of the wind speed, as long as the wind speed increases and the energy consumption of the rotors are improved, it can be achieved. refer to => smartservo.org/en/magnus-vawt-implement-en/

Not even close and never will be.

If there is no wind at all, what's the point of spinning the rotor?

@@praveenb9048 I presume that this system is working without human intervention. So how the wind turbine knows if there's a wind blowing? The electricity is produced by center axis spin by magnus effect produced from 3 rotating "blades"

Yes, I'm assuming that some kind of smart controller would be used. For example, if the wind is to strong the controller would have to reduce the rotor speed to avoid damaging the mechanical and electrical elements.

@@rainbowforest09 Yes, it requires auxiliary devices to make up the system, such as anemometer, controller, batteries or power source ...

@@SmartServo_org Obviously energy is being put in, what is coming out? Hopefully more than in.

Although it has not been proven that the energy output can be greater than the input, it is possible => smartservo.org/en/magnus-vawt-implement-en/ before that, To start the Darrieus turbine is a reasonable work(see ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9AdpggaOfF0.html), when the rotation speed is fast enough, the motor can be stopped(@ 4:03) and no more energy is consumed.

This is for test purpose man. As said in start of test

If you're asking about efficiency, further experimentation is required. I've only verified so far that it can exceed TSR 2, Limited by motor response and rotor lift-to-drag ratio, but already faster than many common VAWTs.

no, this design cannot be achieved, because the motor can't keep up with the frequency of the command.

Since it can produce a lot of torque, I think the power generation is fine, the problem is making it efficient.

Decades ago, people tried to use Magnus rotor to build aircraft, but for many reasons, it failed. In theory, the rotor's lift-drag ratio is not as large as that of fixed-wing, but the lift coefficient is large. Therefore, The speed of the Magnus aircraft is between that of a fixed-wing aircraft and a helicopter. But it can take off and land at short distances, and it still has its value.

@@SmartServo_org I know.

Yes, this helps to some extent.