Rosie, thank you very much for this very helpful video on blade geometry. Can it be that the numerator and denominator of the equation of tan(phi) shown at 4:21 should be flipped?
I really appreciate the time and effort you put into your TH-cam channel. There are quite many people that buy or build small wind turbines and I have seen quite a bit fail by design. My first build was a "One day build with what ever materials you have laying around". A joint venture between me and my 9 year old son. It was the typical small 1 meter radius wind turbine, based on a 3 phase motor from a broken segboard and the the classical wings cut out from a 100 mm PVC pipe. It works, it rotates, it makes (some) power, but it was mostly for fun and teaching. Now I'm hooked, I have bought 3 used blades from Missouri Wind and Solar as the PVC pipe blades has the aerodynamics of a toaster. They work better in strong winds, but what's the fun in buying finished Blades? I plan to design my own blades and even dream of pitch control. But, as you also indicate, its a rabbits hole of things to consider. In my head things has taken off like a SpaceX rocket. I have gotten hold of a free 4 kW Ø100 cm fan that really moves some air. My first thought is...yayyy..I just found a wind tunnel. I know I need to iron out the turbulence, but can I directly take data from a 1:5 scale and use on the full build or will aerodynamics be different in full scale? How long are you in Denmark? The test center from "How to Stop Wind Turbine Blades Hitting the Tower" looks very much like Østerild Testcenter which I visited as of becoming a high school physics teacher. Keep the teaching coming it's really good. :)
Hi Ole! I've been in Denmark nearly 5 years, and you are correct that it was the Østerild Testcenter I visited in a couple of my videos. I looooove it there! That sounds like some really cool engineering you are doing, your son is lucky! I have done some tests with the same (tiny) wind turbine with a fan and outdoors, and the turbulence does make a really, really big difference. The local angle of attack ends up pretty random, so it is hard to design an efficient blade for that. But you know what? I think a home-made wind tunnel is also a fun project, I would love to see what you come up with 😀 You need to consider Reynolds number when you are using a scale model, otherwise your results could be waaaay off a full-scale equivalent. Let me know if you want me to point you in the direction of some information on Reynolds number and how you can design a scale test. And good luck, keep me updated how your project goes!
Just want to say thank you .I've been working in blade industry for more than 15 years , and get some pieces of blade design knowledge . Now I can try more design work myself .
Hey there! I stumbled upon this video while researching wind turbine blades for a university project, and I found your explanation quite insightful. As a university student, my team and I are diving into a research project focused on testing the torque output and drag of an albatross-inspired wind turbine blade inside a wind tunnel. I was intrigued by how the chord length changes and twist angle on standard wind turbine blades are influenced by varying wind speeds along the blade's span, affecting circulation around the airfoil. Our aim is to optimize turbine blades to capture energy at lower wind speeds, hence the focus on torque for the albatross blade, and reduce drag with surface texture changes like dimples. There is existing research on the matter so we're considering manufacturing the blades for testing and even experimenting with adding dimples to one airfoil to observe their impact on torque and drag and the manufacturability using molds an fiberglass lay. Here are a few questions I hoped you could help me with: 1. Since wind tunnel speeds won't vary along the span, would designing and manufacturing a turbine blade with twist angle and chord changes be necessary, or would an extruded airfoil shape suffice for testing purposes? 2. Could we apply the same approach to the albatross-inspired blade? 3. Would measuring lift alone suffice for gathering valuable data on torque produced at lower wind speeds, or do we necessarily need a torque sensor? 4. Are there any other general questions or considerations you'd recommend for our project based on your expertise in wind turbines and blade design? Any insights or guidance you could provide would be greatly appreciated! Thanks in advance!
When I think of wind producing torque , I think of windmills of Holland. I then visualize a beam with a pivot in the middle. I then put 40lbs on one side next to the pivot and then put 40lbs in 10 lbs increments spaced equally apart on the other side. Now imagine a new visualization I put 40lbs next to the pivot on one side and then put 40lbs at the end of the beam on the other side. The design that I think of is nothing like what I see here. Airfoils used for lift makes sense. Thanks for the vid.
Starting with be-cause-effect of Sail Design for Shipping "Devices" energy distribution was a reminder of the history of Sailing, the substitution of human power with the actual Technology that interests Engineering minded people. The Wind Turbine and Solar Panel is another step of Civilisations toward productive Industry. So Networks of HV Cables are like Seaways, Road and Railway Lines, Chain Development Stages of Industrial Development. Interesting for next Generation Education in general.
Hello! The best series ever I've seen about Wind power- the dependencies are explained very well. "machine control of pitch machines" would be a nice topic. One comment: Why do you stay on these ugly Tangler airfoils? The largest problem: their low LE radius. The allowed rougness is proportional by 1/ sqrt(Re). Therefore they are horrible dirt-sensitive. Bec'se the local flow speed around LE is so high that there is an immediate transition. Wortmann made this error 40 years ago on his sailplanes- when there was one fly you needed immediately a wiper.
Very nice video series which gives basics. A lot of great information. Would be nice to see more of that. What I would especially be interested to see is some real life practical examples / calculations for some small wind turbine... 1kW 300W, whatever... Would be great to become more familiar with design process and mindset through practical basic examples
I wonder if there is a design/way to get all the lift force being torque? Seems that with the current designs longer blades are better so as to get the torque component of lift as far from the hub as possible (high rotational speed with thin blades and keeping a constant tip-speed ratio). To illustrate this think of the difference between a sailing boat 'reaching' across the wind compared with it 'pointing' high into the wind. A reaching boat will go much faster that a pointing boat as a much bigger component of the lift force (generated by the sails) is in the direction of travel of the boat.
In a previous video and comment I asked how large would a turbine need to be for a single household. You gave a brilliant answer. My question today, after watching this video is what would that single house hold turbine look like based on your previous answer. Since this would be a substantially smaller unit, would more blades be better? I'd be interested to hear your analysis of what a single household unit would look like based on the various parameters discussed in this video
That's an interesting question, and not so easy to answer here. Maybe it's a good topic for a future video 😊 My short answer is that there are small wind turbines available with both more and less than 3 blades, and it is hard to say which is "better" because the ways to assess performance are not as standardised for small turbines as large ones. When you're designing a small turbine, the requirements are usually different to a utility scale one. Reliability and low maintenance might be your most important requirements and a percent or two of increased output probably don't matter that much. Whereas on a commercial wind farm, even a fraction of a percent increased output is a huge thing. I think the design requirements for small turbines differ a lot from site to site, person to person. And in my opinion, that's why people disagree over what is the "best" design for a small wind turbine.
@@EngineeringwithRosie Brilliant as always, I would look forward to watching said video, if you should ever make it. I'm sure its obvious by now my interest is in dealing with a single household's worth of power because I am looking to reduce my power bill one way or another. I have constructed a variety of devces and have seen what is on the market place, and nothing Ive built or seen on the market is suitable for what I'm looking for. I was hoping that my line of questioning might give me some insight and inspiration as to a better design that may be closer to accomplishing my "goal". I am currently dabbling in construction design using a kids toy known as K'nex. And as entertaining as it has been to construct a variety of designs, I still dont think any of them can get the job done. But I must admit my designs have chaged radically since I first started so it has been a interesting journey. Anywho, Ive chin wagged long enough and just wanted to say thanks for your replies and keep up the great works, I'll be watching. Cheers!
That's an interesting challenge. Where do you live? Suburban, rural, mountains, coast? Wind turbines are generally not as good as solar panels for small and urban/suburban locations. So as much as I love wind energy, and as great as it for large wind farms, it may not be your best choice for your home, if you are purely considering the cost per kWh. But if the plan is also to have a cool engineering project, then I would go for wind energy over solar 😎 mainly because I love aerodynamics and composite materials! Depending on what kind of wind resource you have, you might even consider a vertical axis wind turbine. I have vague plans to build one for my own backyard, because they tend to deal well with turbulent air. But I need to get a backyard first...
wow, nice to see how fluid the optimisations are, and even how they depend on location. That wind on land has to keep tip speed at lower values for noise. .. I wonder: is there any situation where you would go from 3 to 4 wings? Maybe to keep tip speed low on land?
Thanks. but the main reason to decrease the chord length in blade's root is reducing ''wake losses'' which we know it as Schmitz theory in blade design.
Rosie, thanks for the great series. A question on what you say here around 3:54: '... IF the rotational speed stays the same'. Is that an 'if' at all? For a given overall design - including electric generator and gearing within the shaft that links blades to electric generator - is it possible at all to change rotational speed, e.g. to adapt to different wind speed? Or is rotational speed dictated by the need to synchronise the generator to mains AC frequency?
Older wind turbines used to need to rotate at a specific speed to match the grid frequency. More recently though this is no longer needed as an inverter is used to convert the variable frequency from the turbine to the required grid frequency. What made the difference was advances in power electronics that made it economical to build inverters that can handle high power. The same principle is also used in many portable generators nowadays, allowing the engine to run at a variable speed optimised according to the load while at the same time maintaining a constant output frequency of 50Hz or 60Hz as the case may be.
When I first saw a wind turbine, I was a bit surprised at how slim the blades are and how slowly the blades rotate. Since an electric generator's out put is proportional to the rotation speed I would imagine the blades would rotate faster than I actually saw. But It is possible to use gears to speed up the generator rotation but that adds more torque requirement on the rotating blade. So there has to be a trade off. When there is no wind, there will obviously be no rotation. As the wind speeds up the blades start to rotate. So there is a wind speed at which enough torque is generated to start the blades turning. A slimmer blade seems to require high initial wind speed to start it turning? And I wonder how it is and how does it affect the overall efficiency of wind turbine?
Another other question i wanted to ask is when the wind pressure is sometimes very high and we want to control the flow of electricity or just kinetic energy, how can we control the amount of kinetic energy that is being produce by the Wind turbine at the high wind pressure? and what safety precautions should we take before building a wind turbine and use it for our own use at homes and for our farms water motor? I would very thankful to you if you guide me a little bit.
Usually wind turbines have what they call cut-off speeds. You can check that out. Furthermore, a gear system is attached to a wind turbine to regulate electricity generation given different rpms
Hi Rosie, great information about blade profile. Can you come up with a video for run of the mill available materials for the smaller guys looking to develop their own VAWT? PVC tubing, flat shape vs curved or twisted. Thanks. Keep up the awesome videos!
A few things I'd like to know; Is the flow entirely turbulent or is there some laminar flow? If so do you try to extend the laminar flow region? With wind farms how does the wake of the turbine effect others? Can it induce oscillations into turbines? Is the flow from the centre to the tip any worry or concern?
It's actually really hard to figure that out. Large wind turbine manufacturers use a combination of experimental results and computer simulations. It's a lot of work and they still sometimes get surprised by the noise level when the first turbine with a new design is tested. If you are designing a small one of your own I would suggest the fastest way to find it out is to make a prototype with the right blade geometry and rotational velocity and measure it. If you are interested in values for utility scale wind turbines then you can find sound and rotational velocity in the brochures usually.
For VAWT turbines would the airfoil change along the blade length or would there be one airfoil the whole way up? I assume one airfoil because the blade is getting the same wind velocity along the whole length?
Great question and I will have a couple of videos on VAWTs in the next couple of months to talk about the aerodyanmics in more depth, plus the advantages and disadvantages relative to HAWT. You are right, if the blade is straight up and down you don't really need to change the airfoil or taper.
That is a informative video. The thing is that I am going to make a homemade wind turbine in which i wanted to fix the perfect type of blades which are efficient for producing energy, Can you guide me that which type of blades are perfect for a Wind turbine and efficient too and From where can i find them or buy them? I would be very thank full too you.
Another really good, really clear video. But I do have one question... In traditional aircraft wings, it's generally accepted that an elliptical load distribution is the most efficient. I understand the significant differences in things like twist and taper since you're rotating these blades about a central shaft, but my first assumption would be that you'd still be aiming for an elliptical lift distribution in the end. Do you know why these would differ in that respect?
Hi thanks for this informative video. I wanted to ask a question to you that which design of the Wind turbine is best for making a wind turbine in a village type area, and if we don't want to make a big wind turbine like just for our house use and for water motors so how can we minimize the size of the tower and blades? I would be very thankful to you if you guide me.
Thanks for the video! I would appreciate if you could help me with this question, would the turbine require 3 aerofoil sections or is there a possibility of just using one?
You can use one as long as you scale it so a larger chord at the root than the tip, like I explain in the video. The main compromise you'd make in that case would be that you might find it hard to get the stiffness you need at the root with a thin aerodynamic profile.
Rosie in a home wind turbine has anyone given thought to having two turbined of different size blades in tandem, one upwind of the pedestal and one downwind with larger blade diameter to keep everything pointed into the wind? Obviously the downwind turbine will not be as efficient as compared to the upwind turbine due to wind flow turbulence but with a larger diameter blade it should be decent. This concept could only apply to home installations.
Thank you very much for this simple useful content. I have a question please. I am a student in the engineering of renewable energies department and I know the relationships of the length of the chord and the angles of twist and the method of choosing the appropriate aerofoils, but I am wondering: the twisting of the profile takes place around what point?
Thank you! This video is very helpful! I would like to ask for your advice, would a 1.5 MW turbine with a rotor diameter of 110m and hub height of 80m a reasonable application if the average wind speed is 7.03m/s? I am not sure if the dimensions fit in the reasonable range, as I found that usually the diameter is 77-90m?
That wind speed puts the site in class III (low wind speed), so it makes sense that the blades are a bit longer than a turbine with the same rating in a higher wind speed site. I think it sounds reasonable. Of course if you are actually considering buying such a turbine then there are a lot more factors to consider than just this!
Ms Rosie, superb explanation, just a request can you design and fabricate an diy home made blades with easily available materials, that would help lot of diy makers around the world , most design for homemade blades I am seeing is made out of cutting up sewage pipe, I was wondering if an somewhat efficient design can be made out of some other material like aluminium or tin sheet,
So...seeing many utube vids where the person cuts pvc pipe to make blades, but they don't bother to 'close' the 'sides' in order to create the lower camber. I'm a nube to turbines, but I don't know of any propeller or wing that has an 'open', concave bottom. Wouldn't it be better to fill in the pvc blades?
Rosie , thanks for your smart approach about wind turbine blades in general. How can I access your email for further questions on wind turbine blade design, since I am doing my MSc thesis on wind turbine blades.
...what if the rotor and namely horizontal axis will be positioned right angled relative to the wind, so that the thrust will be generated like if it were helicopter rotor, then a airfoil will be more constant along the blade and pushed away from the tower..
Do you mean like a helicopter, or like a water wheel? A helicopter rotor is oriented the same way as a HAWT rotor, isn't it, sort of running "backwards"? Assuming you mean to orient it like a water wheel, I guess you would have two issues. First, that the swept area of wind is likely to be smaller. And second, that the blades angle relative to the wind will be constantly changing as it rotates. e.g. it will be upside down when it is on the far side compared to the front. So you either need to constantly control the blade angle, or you need to cop a big hit to efficiency. It can be done though, and perhaps that configuration could suit certain circumstances well. Is that what you meant, or did I misunderstand your question?
Yep you're right that's a mistake. Thanks for your attention to detail! I will make a correction in the description, I can't change the video unfortunately.
Rosie,what happens when we set a windturbine in the sea? In water? The density of water is almost 1000 times more then the denity of air, right? So, do we have 1000 times more energy then a "wind" turbine??
Yes that's pretty much right. Tidal turbines very closely resemble underwater wind turbines. They have their own unique challenges which have prevented them from going mainstream so far, but there are some interesting tidal techs making progress recently. I ought to do a video on that topic 🙂
@@niconico3907 hello Nico, Well, so as Rosie said : this exist allready, bud thé name for this kind of turbines is "Tidal turbines". They have of course one big negative Point: the speed of the water. Bud positieve Point is the weight of the water is almost 1000 times heavyer then the weight of air. Other positieve Point: they know always the direction of the stream and, the speed. Bud, for more information, search on internet: Tidal turbines.
It is from section 3.7.2 of Burton's "Wind Energy Handbook." amzn.to/32Pb1fh I think I cover the variables in earlier videos in the series, but that will probably be hard to find, so here they are: sigma_r = chord solidity at the radial location (chord length divided by swept circumference at that radial location) lambda = tip speed ratio (tip speed due to blade rotation (radial location times rotational speed) divided by wind speed) C_l = local lift coefficient mu = r/R (radial location divided by radius)
If we connect the Wind Turbines Generator directly to a high voltage direct current power line (assuming it's possible), the rotational speed does not have to be fixed. How much would that help in design and increase efficiency? (Great videos, I have subscribted to your channel immediately!)
Just a thought, have any buddy design a wind blades in 2 parts ,so that the first part near the hub can change angle separate from the tip this will help in transport because the final size will. be larger and it tecnicly will work in winder range of wind,
Yes, look up the GE Cypress wind turbine. It has 2-part blades mostly to help with transport like you suggest. But they are attached rigidly, they can't move independently once they are installed. I think the 2-bladed Envision turbine had an inner and outer section that did move independently in some circumstances, but I am not 100% sure on that. And then, all the old wind turbines that were stall-regulated had tip brakes that moved independently from the rest of the blade. That's actually the topic of my first ever video: th-cam.com/video/Y5T5ZhJQr2o/w-d-xo.html
wind turbine dessingner must take a page from aerospace engine dessing, long blades with variables pitch produce torque when air isn't the speed they were dessing,but if only the 1/3 of the tip move the negative effects are less ,a second choice is to put a hub cone like in the center at least 20 meter in circumference, blades dessing becomes simpler and able to work with a wider range of wind speed ,blades then can be wider at the end were really makes a difference,and ho know lowering rotación speed and additional blades...
No, because the blade is rotating, so the tip sees a higher wind speed (because it's rotational speed is higher) than the root. Does that make sense? If not, tell me what part isn't clear, maybe I can make a simpler video explaining just that part.
Thanks for your comment 🙂 waste is a big issue with modern life, and wind turbines are no exception. I have made a few videos on the topic, check out this playlist: th-cam.com/play/PLJZcg-yztmIYj9c0R9iPq5b6iG-JuEBK7.html
Thanks for the suggestion, I am not sure that I will make another video on this topic but I do have plans to make a website where I have all the information written down with charts and gifs to help explain. Would that be useful for you? Otherwise, you might like to download the video and replay slower. You can do that in VLC player for example, press "[" to playback slower and "]" to speed up.
Long-winded additional information.. The AM-FM Real-time physical manifestation of sync-duration Elemental e-Pi-i superposition Quantum-fields Mechanism Holographic standing wave crystallisation condensation, E=mC² Superspin-symmetry-> Singularity positioning integration, ..is plain-old Atomic Structure WYSIWYG QM-TIME resonance floating, e-Pi-i-numberness compositions. In instantaneous trancendental self-defining cause-effect dimensionality, a complicated manifestation of pure-math relative-timing ratio-rates in conic-cyclonic coherence-cohesion objectives place in time-timing re-evolution Perspective. This is context, Logarithmic quantization calculation of QM-TIME Math-Phys-Chem and Geometry here-now-forever empirical formatting. Astronomical Observation is built around Space-time Spectroscopy of the AM-FM continuous creation connection cause-effect, so just like when a Stroboscopic Timing Light is used to set the Spark and Governor on an ICE motor, much the same idea, in emulation, applies to the analysis of Quantum-fields pulse-evolution Actuality. Theoretical analysis of real-time phenomena is supposed to get all the time-timing sync-duration identification of maintaining and Sciencing Re-search in metastable proportioning probability balance, of re-evolving intelligence, Actual and Artificial.
Thanks for the comment! I think of it as more of a balance rather than a heirarchy. Earlier the aerodynamics/ maths was probably the most important part but now that is well understood the other aspects have more impact. And the order will no doubt change again in the future!
What if there was a better blade design where the "root support", almost 1/3 of the blade that creates no lift, is redesigned to harness this missing life co-efficiency... and the tip was augmented with a noise reduction attachment where no sonic wave could be created or change the rotational speed. What if the blade system itself was "Self-Adjusting" to pockets of wind bursts without creating internal damage or a disruption in the blades performance... Sound impossible... Let me introduce you to... "WyndBlade"...
Oh no! Was my accent hard for you to understand, or too fast? I have uploaded accurate subtitles (not automated) to help if that's the case. Or if it's something else then let me know what.
I like the way how brilliant engineers mingle complicated formulas together and solve the insanely complicated problems to the "goals" of the incredible designs... And at the same time they forget to calculate the relatively simple economic justification showing those "green" wind turbines as actually NOT environment friendly, pollutive in production, weather-dependent, dangerous for live species, spacey, climate-affecting and producing lots of waste - in other words rendering the whole idea as practically hardly worthy, especially in a long run... It always needs another "engineer" (let's call them a "political engineer") to bullshit-talk other people to spend money and resources (not to mention effort and brains) creating and maintaining these beautiful, but utterly ineffective pieces of machinery - a dead-end in the race for "renewable" energy... Amazing! So, maybe, the answer to the question “How Does a Wind Turbine Work?” should be as simple as: "In general - ineffectively and in many cases it simply shouldn't."
How come nobody has ever created a screw like Wind turbine It would capture more wind have higher torque and Of course capture more energy With last waste
This video looks exactly the same as any hostage video ever posted ……lol you need help on framing and set …because I’m pretty sure your not been held captive….are you ???
Rosie, thank you very much for this very helpful video on blade geometry. Can it be that the numerator and denominator of the equation of tan(phi) shown at 4:21 should be flipped?
soh cah toa.... yep it does look like I flipped that. Lucky you were paying attention! I can't change it unfortunately, once it's posted.
I really appreciate the time and effort you put into your TH-cam channel. There are quite many people that buy or build small wind turbines and I have seen quite a bit fail by design. My first build was a "One day build with what ever materials you have laying around". A joint venture between me and my 9 year old son. It was the typical small 1 meter radius wind turbine, based on a 3 phase motor from a broken segboard and the the classical wings cut out from a 100 mm PVC pipe. It works, it rotates, it makes (some) power, but it was mostly for fun and teaching.
Now I'm hooked, I have bought 3 used blades from Missouri Wind and Solar as the PVC pipe blades has the aerodynamics of a toaster. They work better in strong winds, but what's the fun in buying finished Blades? I plan to design my own blades and even dream of pitch control. But, as you also indicate, its a rabbits hole of things to consider. In my head things has taken off like a SpaceX rocket. I have gotten hold of a free 4 kW Ø100 cm fan that really moves some air. My first thought is...yayyy..I just found a wind tunnel. I know I need to iron out the turbulence, but can I directly take data from a 1:5 scale and use on the full build or will aerodynamics be different in full scale?
How long are you in Denmark? The test center from "How to Stop Wind Turbine Blades Hitting the Tower" looks very much like Østerild Testcenter which I visited as of becoming a high school physics teacher.
Keep the teaching coming it's really good. :)
Hi Ole! I've been in Denmark nearly 5 years, and you are correct that it was the Østerild Testcenter I visited in a couple of my videos. I looooove it there!
That sounds like some really cool engineering you are doing, your son is lucky! I have done some tests with the same (tiny) wind turbine with a fan and outdoors, and the turbulence does make a really, really big difference. The local angle of attack ends up pretty random, so it is hard to design an efficient blade for that. But you know what? I think a home-made wind tunnel is also a fun project, I would love to see what you come up with 😀
You need to consider Reynolds number when you are using a scale model, otherwise your results could be waaaay off a full-scale equivalent. Let me know if you want me to point you in the direction of some information on Reynolds number and how you can design a scale test. And good luck, keep me updated how your project goes!
Just want to say thank you .I've been working in blade industry for more than 15 years , and get some pieces of blade design knowledge . Now I can try more design work myself .
Hey there! I stumbled upon this video while researching wind turbine blades for a university project, and I found your explanation quite insightful. As a university student, my team and I are diving into a research project focused on testing the torque output and drag of an albatross-inspired wind turbine blade inside a wind tunnel.
I was intrigued by how the chord length changes and twist angle on standard wind turbine blades are influenced by varying wind speeds along the blade's span, affecting circulation around the airfoil.
Our aim is to optimize turbine blades to capture energy at lower wind speeds, hence the focus on torque for the albatross blade, and reduce drag with surface texture changes like dimples. There is existing research on the matter so we're considering manufacturing the blades for testing and even experimenting with adding dimples to one airfoil to observe their impact on torque and drag and the manufacturability using molds an fiberglass lay.
Here are a few questions I hoped you could help me with:
1. Since wind tunnel speeds won't vary along the span, would designing and manufacturing a turbine blade with twist angle and chord changes be necessary, or would an extruded airfoil shape suffice for testing purposes?
2. Could we apply the same approach to the albatross-inspired blade?
3. Would measuring lift alone suffice for gathering valuable data on torque produced at lower wind speeds, or do we necessarily need a torque sensor?
4. Are there any other general questions or considerations you'd recommend for our project based on your expertise in wind turbines and blade design?
Any insights or guidance you could provide would be greatly appreciated! Thanks in advance!
When I think of wind producing torque , I think of windmills of Holland. I then visualize a beam with a pivot in the middle. I then put 40lbs on one side next to the pivot and then put 40lbs in 10 lbs increments spaced equally apart on the other side. Now imagine a new visualization I put 40lbs next to the pivot on one side and then put 40lbs at the end of the beam on the other side. The design that I think of is nothing like what I see here. Airfoils used for lift makes sense. Thanks for the vid.
Starting with be-cause-effect of Sail Design for Shipping "Devices" energy distribution was a reminder of the history of Sailing, the substitution of human power with the actual Technology that interests Engineering minded people.
The Wind Turbine and Solar Panel is another step of Civilisations toward productive Industry. So Networks of HV Cables are like Seaways, Road and Railway Lines, Chain Development Stages of Industrial Development.
Interesting for next Generation Education in general.
This has cleared this up for me. Thank you Rosie, great video.
you're a great teacher
Congratulations! This is the one of best explanation in this topic
this videos are an absolute pleasure and exactly what i was looking for. thank you for this super high quality content
It’s so much knowledge in only one video! Thank You! For this kind of essential
Glad it was helpful!
Hello! The best series ever I've seen about Wind power- the dependencies are explained very well.
"machine control of pitch machines" would be a nice topic.
One comment: Why do you stay on these ugly Tangler airfoils?
The largest problem: their low LE radius. The allowed rougness is proportional by 1/ sqrt(Re). Therefore they are horrible dirt-sensitive. Bec'se the local flow speed around LE is so high that there is an immediate transition. Wortmann made this error 40 years ago on his sailplanes- when there was one fly you needed immediately a wiper.
Can you go through an example of how to design a blade? Please 🙏 this is incredible to listen to
THANKS FOR USEFUL information! Appreciate!
Very nice video series which gives basics. A lot of great information. Would be nice to see more of that. What I would especially be interested to see is some real life practical examples / calculations for some small wind turbine... 1kW 300W, whatever... Would be great to become more familiar with design process and mindset through practical basic examples
Thank you so much to share very educational video tutorial
I wonder if there is a design/way to get all the lift force being torque? Seems that with the current designs longer blades are better so as to get the torque component of lift as far from the hub as possible (high rotational speed with thin blades and keeping a constant tip-speed ratio). To illustrate this think of the difference between a sailing boat 'reaching' across the wind compared with it 'pointing' high into the wind. A reaching boat will go much faster that a pointing boat as a much bigger component of the lift force (generated by the sails) is in the direction of travel of the boat.
In a previous video and comment I asked how large would a turbine need to be for a single household. You gave a brilliant answer. My question today, after watching this video is what would that single house hold turbine look like based on your previous answer. Since this would be a substantially smaller unit, would more blades be better? I'd be interested to hear your analysis of what a single household unit would look like based on the various parameters discussed in this video
That's an interesting question, and not so easy to answer here. Maybe it's a good topic for a future video 😊
My short answer is that there are small wind turbines available with both more and less than 3 blades, and it is hard to say which is "better" because the ways to assess performance are not as standardised for small turbines as large ones.
When you're designing a small turbine, the requirements are usually different to a utility scale one. Reliability and low maintenance might be your most important requirements and a percent or two of increased output probably don't matter that much. Whereas on a commercial wind farm, even a fraction of a percent increased output is a huge thing.
I think the design requirements for small turbines differ a lot from site to site, person to person. And in my opinion, that's why people disagree over what is the "best" design for a small wind turbine.
@@EngineeringwithRosie Brilliant as always, I would look forward to watching said video, if you should ever make it. I'm sure its obvious by now my interest is in dealing with a single household's worth of power because I am looking to reduce my power bill one way or another. I have constructed a variety of devces and have seen what is on the market place, and nothing Ive built or seen on the market is suitable for what I'm looking for. I was hoping that my line of questioning might give me some insight and inspiration as to a better design that may be closer to accomplishing my "goal". I am currently dabbling in construction design using a kids toy known as K'nex. And as entertaining as it has been to construct a variety of designs, I still dont think any of them can get the job done. But I must admit my designs have chaged radically since I first started so it has been a interesting journey. Anywho, Ive chin wagged long enough and just wanted to say thanks for your replies and keep up the great works, I'll be watching. Cheers!
@@EngineeringwithRosie Oh by the way, i think you might find this interesting. Cheers! th-cam.com/video/_QLEERYS5C8/w-d-xo.html
@@EngineeringwithRosie This looks promising th-cam.com/video/BF7yX-7Wy30/w-d-xo.html
That's an interesting challenge. Where do you live? Suburban, rural, mountains, coast? Wind turbines are generally not as good as solar panels for small and urban/suburban locations. So as much as I love wind energy, and as great as it for large wind farms, it may not be your best choice for your home, if you are purely considering the cost per kWh.
But if the plan is also to have a cool engineering project, then I would go for wind energy over solar 😎 mainly because I love aerodynamics and composite materials!
Depending on what kind of wind resource you have, you might even consider a vertical axis wind turbine. I have vague plans to build one for my own backyard, because they tend to deal well with turbulent air. But I need to get a backyard first...
wow, nice to see how fluid the optimisations are, and even how they depend on location. That wind on land has to keep tip speed at lower values for noise.
.. I wonder: is there any situation where you would go from 3 to 4 wings? Maybe to keep tip speed low on land?
heyy can I get the pdf you have in this video. You mention that it will be in the description but I cant find it.
Thanks. but the main reason to decrease the chord length in blade's root is reducing ''wake losses'' which we know it as Schmitz theory in blade design.
Hi Rosie, Thank you for your sharing the knowledge. Can tell is about control parameters of turbulence
Is the area of the rotor included in the swept disc area or is it just the area that the blades themselves cover?
amazing video friend
Thanks! I'm glad it was helpful for you.
@@EngineeringwithRosie Have you done a video comparing gearbox to direct drive?
Rosie, thanks for the great series. A question on what you say here around 3:54: '... IF the rotational speed stays the same'.
Is that an 'if' at all?
For a given overall design - including electric generator and gearing within the shaft that links blades to electric generator - is it possible at all to change rotational speed, e.g. to adapt to different wind speed? Or is rotational speed dictated by the need to synchronise the generator to mains AC frequency?
Older wind turbines used to need to rotate at a specific speed to match the grid frequency. More recently though this is no longer needed as an inverter is used to convert the variable frequency from the turbine to the required grid frequency. What made the difference was advances in power electronics that made it economical to build inverters that can handle high power.
The same principle is also used in many portable generators nowadays, allowing the engine to run at a variable speed optimised according to the load while at the same time maintaining a constant output frequency of 50Hz or 60Hz as the case may be.
2:50 at a steady state. More mass as well may adversly effect transition processes🕵️😁🏋️🤝🤫
will adding Winglets to the end of the blades help with the efficiency or even to control the yaw?
Thank you very much for the information. Can you please tell me that related (optimal) Naca profiles for Root,Mid and tip ?
I have a question. How does angle of attack theoretically influence thrust and propulsion efficiency?
When I first saw a wind turbine, I was a bit surprised at how slim the blades are and how slowly the blades rotate. Since an electric generator's out put is proportional to the rotation speed I would imagine the blades would rotate faster than I actually saw. But It is possible to use gears to speed up the generator rotation but that adds more torque requirement on the rotating blade. So there has to be a trade off.
When there is no wind, there will obviously be no rotation. As the wind speeds up the blades start to rotate. So there is a wind speed at which enough torque is generated to start the blades turning. A slimmer blade seems to require high initial wind speed to start it turning? And I wonder how it is and how does it affect the overall efficiency of wind turbine?
Another other question i wanted to ask is when the wind pressure is sometimes very high and we want to control the flow of electricity or just kinetic energy, how can we control the amount of kinetic energy that is being produce by the Wind turbine at the high wind pressure? and what safety precautions should we take before building a wind turbine and use it for our own use at homes and for our farms water motor?
I would very thankful to you if you guide me a little bit.
Usually wind turbines have what they call cut-off speeds. You can check that out. Furthermore, a gear system is attached to a wind turbine to regulate electricity generation given different rpms
Please go into the electrical generation and line synchronization and power factor.
Hi Rosie, great information about blade profile.
Can you come up with a video for run of the mill available materials for the smaller guys looking to develop their own VAWT? PVC tubing, flat shape vs curved or twisted.
Thanks. Keep up the awesome videos!
Hello Dr. Rosie
Could you please tell me which is the best and simple software that helps me to design the wind turbine blades?
If I am making a cad model what material should I give for blade ??
A few things I'd like to know;
Is the flow entirely turbulent or is there some laminar flow? If so do you try to extend the laminar flow region?
With wind farms how does the wake of the turbine effect others? Can it induce oscillations into turbines?
Is the flow from the centre to the tip any worry or concern?
Thank you for your video, it's super helpful! However, how do I know how much rotational speed will exert how much sound level?
It's actually really hard to figure that out. Large wind turbine manufacturers use a combination of experimental results and computer simulations. It's a lot of work and they still sometimes get surprised by the noise level when the first turbine with a new design is tested. If you are designing a small one of your own I would suggest the fastest way to find it out is to make a prototype with the right blade geometry and rotational velocity and measure it.
If you are interested in values for utility scale wind turbines then you can find sound and rotational velocity in the brochures usually.
There is a large NASA reference publication 1218 about sound generatoion available on the net. Airfoil self noise and prediction.
Hi Rosie where can I find the math behind the blade geometry design? like the ones in the book you showed in your video?
For VAWT turbines would the airfoil change along the blade length or would there be one airfoil the whole way up? I assume one airfoil because the blade is getting the same wind velocity along the whole length?
Great question and I will have a couple of videos on VAWTs in the next couple of months to talk about the aerodyanmics in more depth, plus the advantages and disadvantages relative to HAWT. You are right, if the blade is straight up and down you don't really need to change the airfoil or taper.
@@EngineeringwithRosie I really look forward to those videos! I am trying to design a helical VAWT, would one airfoil the whole way up be okay?
@@simplykatie98 yes. if it were an "egg beater" darrius style vawt then you would want to blend profiles.
That is a informative video. The thing is that I am going to make a homemade wind turbine in which i wanted to fix the perfect type of blades which are efficient for producing energy, Can you guide me that which type of blades are perfect for a Wind turbine and efficient too and From where can i find them or buy them?
I would be very thank full too you.
Another really good, really clear video. But I do have one question... In traditional aircraft wings, it's generally accepted that an elliptical load distribution is the most efficient. I understand the significant differences in things like twist and taper since you're rotating these blades about a central shaft, but my first assumption would be that you'd still be aiming for an elliptical lift distribution in the end. Do you know why these would differ in that respect?
How about matching the rotor with a generator?
Hi thanks for this informative video. I wanted to ask a question to you that which design of the Wind turbine is best for making a wind turbine in a village type area, and if we don't want to make a big wind turbine like just for our house use and for water motors so how can we minimize the size of the tower and blades?
I would be very thankful to you if you guide me.
Q blade is amazing software that helps with this
Thanks for the video! I would appreciate if you could help me with this question, would the turbine require 3 aerofoil sections or is there a possibility of just using one?
You can use one as long as you scale it so a larger chord at the root than the tip, like I explain in the video. The main compromise you'd make in that case would be that you might find it hard to get the stiffness you need at the root with a thin aerodynamic profile.
@@EngineeringwithRosie ok, thank you for the help!
Rosie in a home wind turbine has anyone given thought to having two turbined of different size blades in tandem, one upwind of the pedestal and one downwind with larger blade diameter to keep everything pointed into the wind? Obviously the downwind turbine will not be as efficient as compared to the upwind turbine due to wind flow turbulence but with a larger diameter blade it should be decent. This concept could only apply to home installations.
Thank you very much for this simple useful content.
I have a question please.
I am a student in the engineering of renewable energies department and I know the relationships of the length of the chord and the angles of twist and the method of choosing the appropriate aerofoils, but I am wondering: the twisting of the profile takes place around what point?
hello mam . i am doing research on wind turbine blade in my PhD . kindly tell me some area where i can get work.
Thank you! This video is very helpful! I would like to ask for your advice, would a 1.5 MW turbine with a rotor diameter of 110m and hub height of 80m a reasonable application if the average wind speed is 7.03m/s? I am not sure if the dimensions fit in the reasonable range, as I found that usually the diameter is 77-90m?
That wind speed puts the site in class III (low wind speed), so it makes sense that the blades are a bit longer than a turbine with the same rating in a higher wind speed site. I think it sounds reasonable. Of course if you are actually considering buying such a turbine then there are a lot more factors to consider than just this!
Ms Rosie, superb explanation, just a request can you design and fabricate an diy home made blades with easily available materials, that would help lot of diy makers around the world , most design for homemade blades I am seeing is made out of cutting up sewage pipe, I was wondering if an somewhat efficient design can be made out of some other material like aluminium or tin sheet,
That's a good idea, I will see when I can find the time to work on that project 😊
So...seeing many utube vids where the person cuts pvc pipe to make blades, but they don't bother to 'close' the 'sides' in order to create the lower camber. I'm a nube to turbines, but I don't know of any propeller or wing that has an 'open', concave bottom. Wouldn't it be better to fill in the pvc blades?
Rosie , thanks for your smart approach about wind turbine blades in general. How can I access your email for further questions on wind turbine blade design, since I am doing my MSc thesis on wind turbine blades.
...what if the rotor and namely horizontal axis will be positioned right angled relative to the wind, so that the thrust will be generated like if it were helicopter rotor, then a airfoil will be more constant along the blade and pushed away from the tower..
Do you mean like a helicopter, or like a water wheel? A helicopter rotor is oriented the same way as a HAWT rotor, isn't it, sort of running "backwards"?
Assuming you mean to orient it like a water wheel, I guess you would have two issues. First, that the swept area of wind is likely to be smaller. And second, that the blades angle relative to the wind will be constantly changing as it rotates. e.g. it will be upside down when it is on the far side compared to the front. So you either need to constantly control the blade angle, or you need to cop a big hit to efficiency. It can be done though, and perhaps that configuration could suit certain circumstances well.
Is that what you meant, or did I misunderstand your question?
How does a wind turbine work at variable speeds if the generator needs to be synched to grid frequency? Obviously there is a way, but what is it?
Why does tan(phi)=omega r(1+a')/u(1-a) and not =u(1-a)/omega r(1+a'). surely tan=opposite/adjacent?
Yep you're right that's a mistake. Thanks for your attention to detail!
I will make a correction in the description, I can't change the video unfortunately.
the airfoil sections in your drawings at the beginning of the movie seem to be the wrong way round (180 degrees)...
Rosie,what happens when we set a windturbine in the sea? In water? The density of water is almost 1000 times more then the denity of air, right? So, do we have 1000 times more energy then a "wind" turbine??
Yes that's pretty much right. Tidal turbines very closely resemble underwater wind turbines. They have their own unique challenges which have prevented them from going mainstream so far, but there are some interesting tidal techs making progress recently. I ought to do a video on that topic 🙂
No, because water doesn't move as fast as air, and power is proportional to the square of the speed.
@@niconico3907 hello Nico, Well, so as Rosie said : this exist allready, bud thé name for this kind of turbines is "Tidal turbines". They have of course one big negative Point: the speed of the water. Bud positieve Point is the weight of the water is almost 1000 times heavyer then the weight of air. Other positieve Point: they know always the direction of the stream and, the speed. Bud, for more information, search on internet: Tidal turbines.
At the equation shown at 6;17 talking about Optimum Aerodynamic Design, what do each of the variables mean? I was unsure it this was covered.
It is from section 3.7.2 of Burton's "Wind Energy Handbook."
amzn.to/32Pb1fh
I think I cover the variables in earlier videos in the series, but that will probably be hard to find, so here they are:
sigma_r = chord solidity at the radial location (chord length divided by swept circumference at that radial location)
lambda = tip speed ratio (tip speed due to blade rotation (radial location times rotational speed) divided by wind speed)
C_l = local lift coefficient
mu = r/R (radial location divided by radius)
If we connect the Wind Turbines Generator directly to a high voltage direct current power line (assuming it's possible), the rotational speed does not have to be fixed. How much would that help in design and increase efficiency? (Great videos, I have subscribted to your channel immediately!)
Just a thought, have any buddy design a wind blades in 2 parts ,so that the first part near the hub can change angle separate from the tip this will help in transport because the final size will. be larger and it tecnicly will work in winder range of wind,
Yes, look up the GE Cypress wind turbine. It has 2-part blades mostly to help with transport like you suggest. But they are attached rigidly, they can't move independently once they are installed. I think the 2-bladed Envision turbine had an inner and outer section that did move independently in some circumstances, but I am not 100% sure on that. And then, all the old wind turbines that were stall-regulated had tip brakes that moved independently from the rest of the blade. That's actually the topic of my first ever video: th-cam.com/video/Y5T5ZhJQr2o/w-d-xo.html
wind turbine dessingner must take a page from aerospace engine dessing, long blades with variables pitch produce torque when air isn't the speed they were dessing,but if only the 1/3 of the tip move the negative effects are less ,a second choice is to put a hub cone like in the center at least 20 meter in circumference, blades dessing becomes simpler and able to work with a wider range of wind speed ,blades then can be wider at the end were really makes a difference,and ho know lowering rotación speed and additional blades...
thanks
Wouldn’t wind speed affect every airfoil the same?
No, because the blade is rotating, so the tip sees a higher wind speed (because it's rotational speed is higher) than the root. Does that make sense? If not, tell me what part isn't clear, maybe I can make a simpler video explaining just that part.
You didn't mention variable pitch
Those designs will look cool in 10 to 20 years in landfills all over America.
Thanks for your comment 🙂 waste is a big issue with modern life, and wind turbines are no exception. I have made a few videos on the topic, check out this playlist:
th-cam.com/play/PLJZcg-yztmIYj9c0R9iPq5b6iG-JuEBK7.html
Great information and much appreciated. I enjoy your presentation but can't help wondering if as you are speaking someone is tickling your toes?😁
Hello there. I really like your video's but can you please show the pictures a little bit longer?
Go to settings and change the playback speed
Please make one slow video on why blades are twisted with simple sketches and animations.Pls don't go too fast.
Thanks for the suggestion, I am not sure that I will make another video on this topic but I do have plans to make a website where I have all the information written down with charts and gifs to help explain. Would that be useful for you?
Otherwise, you might like to download the video and replay slower. You can do that in VLC player for example, press "[" to playback slower and "]" to speed up.
@@EngineeringwithRosie thanks...website would be great..
Long-winded additional information..
The AM-FM Real-time physical manifestation of sync-duration Elemental e-Pi-i superposition Quantum-fields Mechanism Holographic standing wave crystallisation condensation, E=mC² Superspin-symmetry-> Singularity positioning integration, ..is plain-old Atomic Structure WYSIWYG QM-TIME resonance floating, e-Pi-i-numberness compositions. In instantaneous trancendental self-defining cause-effect dimensionality, a complicated manifestation of pure-math relative-timing ratio-rates in conic-cyclonic coherence-cohesion objectives place in time-timing re-evolution Perspective. This is context, Logarithmic quantization calculation of QM-TIME Math-Phys-Chem and Geometry here-now-forever empirical formatting.
Astronomical Observation is built around Space-time Spectroscopy of the AM-FM continuous creation connection cause-effect, so just like when a Stroboscopic Timing Light is used to set the Spark and Governor on an ICE motor, much the same idea, in emulation, applies to the analysis of Quantum-fields pulse-evolution Actuality.
Theoretical analysis of real-time phenomena is supposed to get all the time-timing sync-duration identification of maintaining and Sciencing Re-search in metastable proportioning probability balance, of re-evolving intelligence, Actual and Artificial.
Spanish subtitle?
so line up is
material
manufacturing
environmental limits
math
Thanks for the comment! I think of it as more of a balance rather than a heirarchy. Earlier the aerodynamics/ maths was probably the most important part but now that is well understood the other aspects have more impact. And the order will no doubt change again in the future!
Perhaps you could show a few actual blades in your how to design blades video.
What if there was a better blade design where the "root support", almost 1/3 of the blade that creates no lift, is redesigned to harness this missing life co-efficiency... and the tip was augmented with a noise reduction attachment where no sonic wave could be created or change the rotational speed. What if the blade system itself was "Self-Adjusting" to pockets of wind bursts without creating internal damage or a disruption in the blades performance... Sound impossible... Let me introduce you to... "WyndBlade"...
Kidding leonartydo 500 + year old new on left no gaps full on
I thought I could speak English, silly me.
Oh no! Was my accent hard for you to understand, or too fast? I have uploaded accurate subtitles (not automated) to help if that's the case. Or if it's something else then let me know what.
@@EngineeringwithRosie oh no , it was me lacking few definitions then pausing the video to google it , thank You for the opportunity to learn 8)
I like the way how brilliant engineers mingle complicated formulas together and solve the insanely complicated problems to the "goals" of the incredible designs... And at the same time they forget to calculate the relatively simple economic justification showing those "green" wind turbines as actually NOT environment friendly, pollutive in production, weather-dependent, dangerous for live species, spacey, climate-affecting and producing lots of waste - in other words rendering the whole idea as practically hardly worthy, especially in a long run...
It always needs another "engineer" (let's call them a "political engineer") to bullshit-talk other people to spend money and resources (not to mention effort and brains) creating and maintaining these beautiful, but utterly ineffective pieces of machinery - a dead-end in the race for "renewable" energy... Amazing!
So, maybe, the answer to the question “How Does a Wind Turbine Work?” should be as simple as: "In general - ineffectively and in many cases it simply shouldn't."
😂
it`s hard to follow because we always see your face, i want to see the grafics
What so funny?
Her boyfriend must have been doing stuff to her below.
How come nobody has ever created a screw like Wind turbine It would capture more wind have higher torque and Of course capture more energy With last waste
This video looks exactly the same as any hostage video ever posted ……lol you need help on framing and set …because I’m pretty sure your not been held captive….are you ???
THis is all for HAWT blades tho