The possible approaches for VWAT simulation: 1. Cascade model+Leishman-Beddoes dynamic stall model. 2. Double Multiple Stream Tube model. 3. 2D Point vortex +Leishman-Beddoes dynamic stall model+free wake model. 4. Lift line model + +Leishman-Beddoes dynamic stall model+free wake model or vortex in cell method to deal with the complexity of wake. 5. Unsteady free wake Vortex Lattice Method (VLM) or Panel method. 6. CFD methods based on sliding mesh or overset mesh technique and URANS.

@EngineeringwithRosie

3 жыл бұрын

Thanks for adding this information! It's complicated, isn't it?

@johnluffman7954

3 жыл бұрын

@@EngineeringwithRosie Yeah. It needs a lot of effort.

@les8489

3 жыл бұрын

Choice of method depends on solidity...for high solidity a relatively simple approach is the cascade model with stall and flow curvature accounted for. CFD - yes, if you have software and a fast comp. Lift line works well - a good example is QBlade.

@rashidisw

3 жыл бұрын

How about adding a hollow funnel/cone-like structure located below the VAWT? I remember seeing a patent describing it about two decades ago. The patent claims the cone structure would allow to re-focusing the wind/air-flow that coming from opening located on bottom part of the cone, the focused air-flow then used to turn the already spinning VAWT, further increasing its output.

@kahlernygard809

3 жыл бұрын

@@rashidisw a university in England just did the math and find if you position the vawts right they are more efficient than the big wind turbines on a large scale. Vawts are the future and the only certified one is the hivawt. This technology has been surpressed by Facebook and the government

Can you make the video of the maths and theory of aerodynamic analysis of a VAWT

@EngineeringwithRosie

3 жыл бұрын

Thanks for your comment, if I get a lot of people asking or liking your comment then I will make one! So far there are two of you who want to see more maths 😁😁

@jackz1620

3 жыл бұрын

Would love to see a video on the theory as well. Thanks! Also have you seen the parachute idea of utilizing wind power? Something like skysails?

@sawanyboy

3 жыл бұрын

Yes would appreciate if give detail theories and math on this.

@backyardworker

3 жыл бұрын

@@EngineeringwithRosie I just found this by accident. And probably by KZread algorithm secrets... 😉 I would be very, very interested in some more maths behind. I need the for-dummies-version, though. If that is at all possible. Non the less, I think something like this should be on every roof. Even if it's just at 20-30% efficiency with a small battery backup. This could help to keep the fridge running if the power is out for a slightly longer time. And with more and more tech in every home, a small power backup would help save equipment and files by giving people time to shut down their computers, etc. Compared to a horizontal wind turbine, a vertical design is probably much better suited to install on the roofs in an urban environment.

@rabazelbarredo4447

3 жыл бұрын

I think 60 likes is a lot :)

These videos are gold dust. This is what KZread should be like as a norm. Authoritative and clear and no fear of the use of maths. Thanks a lot.

@thetroopersk

Жыл бұрын

sometimes math doesntwork in reallife

I'm a newbe - sent here by Dave Borlace of "Just Have A Think". Great content - thanks!!

@global_nomad.

3 жыл бұрын

me too...

@sandyfordd1843

3 жыл бұрын

@@global_nomad. , me three.

@alanmcrae8594

3 жыл бұрын

us, four & five...

@blueslsd

3 жыл бұрын

Me to

@TheMadMagician87

3 жыл бұрын

Ditto.

I understood about 1 percent of this but was fascinated enough to stay to the end. Thank you for providing me with much needed rest time.

give us the math!!!! i love your work. it is verry inspiring

@EngineeringwithRosie

3 жыл бұрын

Thank you! I will add your vote to the "yes to maths" column 😁

@007hansen

3 жыл бұрын

@@EngineeringwithRosie maybe even with Modelica, so we can use the math you did 😆

@milandjuric8043

3 жыл бұрын

Yes to math over here too

@johnswolter

3 жыл бұрын

Yes, I want all the references citations & books. As an Aerospace Engineer with access to CFD codes from my desktop computer, analyzing a number of different VAWT designs is easy. "Cry, Havoc! Let slip the dogs of design", Unfurl the knowledge to the winds, the unexpected will happen. JSW

@yanickgenest1324

3 жыл бұрын

YES ! Bring the MATH ! :P Jokes aside, I would be interested too !

Ive recently moved to a windy off grid location and have been wondering about VAWTs to make use of that wind, it seemed so simple to build in that the wind direction doesn't matter but it turns out there's a lot more to it than just the wind direction and length of the blades! Thanks for breaking it down so succinctly!

I have been a designer/consultant/inventor for many years and just wanted to say thank you

Great Video!! I'm Currently in my final year at university and I'm working on developing the Double Multiple Stream Tube model (DMST) to analyse VAWT turbine performance. So, I'm voting for this for the next video!!! Would love to see your breakdown of it, seen as it's an extension of this video. Or even the single/multiple tube model.

@EngineeringwithRosie

3 жыл бұрын

Hey wow, big project. Good luck! You will know more about it than me if you've been researching for a while, I should be asking you for advice! It takes me months to research and finish a new video, so likely you will be finished before I get to it, which means it wouldn't be much help to you unfortunately. I would be interested to see your project though, so please post a link when you're done (and tag me so I get notified).

Halfway through the video I was saying to myself "control the blade angle like a helicopter!" I'm glad that was validated at the end haha.

@gkdresden

3 жыл бұрын

There is more effort than in the case of main rotor control mechanism of a helicopter, because: - the wind can come from every direction - each blade must be controlled individually within the whole cycle of revolution. The first idea i had is to use 2 rotor axes separated by half of the blade width from a single axis which can be turned into wind direction. The blades overspan the distance between the axes and are therefore always in the correct angle to the wind, no matter where they are within the cycle of revolution. Maybe, Rosie can comment on this.

@GoatZilla

3 жыл бұрын

Kind of seems like they just need the fastest feedback mechanism and some sort of PID control. There are some DIY projects out there for instance that are used for balancing brushless motors and props, using sensors to tell you exactly where the motor/prop is unbalanced.

@jph219

3 жыл бұрын

To me an actively assisted passive pitch guidance system should be feasible. Put a cam on the central shaft with control rods to the blades. Rotate the cam with wind direction ...

@Taygetea

3 жыл бұрын

@@jph219 Oh that's very elegant, I like it.

@ratgreen

3 жыл бұрын

@@jph219 Eaxctly what I came here to comment.

Great presentation! Nice to see someone not treating me like an idiot when explaining something. As I see it, the biggest ADVANTAGE of VAWT is having the "guts" at ground level. The biggest DISADVANTAGE of the Darius-style is that they're not self-starting - but that can be fixed by having a Savonius-style starter turbine.

Luckily, I found both videos in April 2021. After Part 1, I was very eager to hear about potential designs. This is such a useful pair of videos. Thanks!

Great lecture! I wouldn't have thought I can understand the workings of these turbines in 12 minutes.

Great video !! I'm a retired mechanical engineer and I'm building my dream ranch totally off grid and as much recycled materials as posible. I've built a vawt at my off grid home to suppliment the solar system. I've tried several airfoil shapes and materials most of which have failed. I've studied that vawt are self governing and with our near constant wind here and gusts up to 80mph, that's a plus. At the moment I've settled on 55 gallon drums cut in half as I hope to make this easy and inexpensive to replicate for the Free seminars I plan to give this year. I live in the poorest county in the U.S. and want to give hope to those who have very little and build their self esteem and confidence. We also have outrageous electric costs !! I have a total of $30 invested and my smart drive washing machine alternator/ motor makes 27 volts and 10amps in a 15 mph breeze. All of the design work I owe to the University of U-Tube and thanks for you and everyone sharing your skills to help the world. Charlie

@RedBatteryHead

2 жыл бұрын

Awesome you are able to sustain yourself. That's all you need to do in on order to get out of the energy money pit we're going to fall for now.

@charleshughbryan5603

2 жыл бұрын

@@RedBatteryHead Hello and thanks for your reply. I used to build nuke plants and high rise buildings in Chicago. I sold my $400,000 dream house,( the greenest house in the state) and moved to northern AZ in 2014. Now that my children are off on their own, I get to live out my dreams of minimalist, self sustainable living. I have community water and power on my lot line but will never tie into it. I refuse to become a consumer !! I'm finishing up a pure hydrogen fuel cell as I received the grapheen last week. I've had good results with HHO but couldn't produce enough to run my car 100% on it and so had to run gas also. The mileage went from 44 to 54 mpg but this new system won't be on demand on the vehicle. I'll make pure hydrogen from my solar powered system and compress it into an old LP tank and use quick air couplers to put into the car and drive away by turning off the gas pump and using it as back up power when the hydrogen runs out. I'll also use it for my back up generator in tandem with solar and windmill power. I can't wait to get up every morning and get to work !! I really appreciate the University of U-Tube as so many great people are sharing ideas. I learn something new every day.

@RedBatteryHead

2 жыл бұрын

@@charleshughbryan5603 better use PV and swap to a BEV. Makes the most use of your electrons.

@charleshughbryan5603

2 жыл бұрын

@@RedBatteryHead Thanks for the tip but I'm recycling all I can here and found 250 watt panels for $50 each. I'm trying to repurpose as much as possible as folks here are hanging on by their fingernails and I want them to be able to replicate all I have. I was an electrician in the Marines but mechanical is more my strong suit. I believe I can blunder my way through showing folks how to install a simple system. I'm building a tracking system for mine as I've heard a gain of 30% is possible.

Hi Rosie! Thank you so much for all of your amazing videos! I started working for a company which supplies composite foams and balsas to LM Wind. Through that I was able to learn about and nerd out over wind turbines and specifically the blades. I'm currently in the Rocky Mountains, USA. I think that locally we could harvest a lot of ancient and modern ideas for green environmental control. For instance I have been really interested in Persian Qanats and ancient evaporative cooling techniques. I've been thinking about, for instance, having a qanat where each wind-catching tower has a VAWT atop it- the fluid dynamics of the qanat help cool interiors while the VAWTS atop a qanat tower might assist with pumping needs or maintenance of the qanat itself! Climate change is sadly irreversible and I neither an engineer nor a prepper but I am really interested in learning how to harness energy in nature to help us all survive in the future. Thank you Rosie for your awesome videos and inspiring content!

Nice! You're the real deal obviously. Tricky stuff, plain language, clear take home messages that even I get. Would love a more mathematical vid though it'd be mostly lost on me. Keep doing your thing.

Thank you for the practical analysis. We are indeed considering the VAWT for urban Distributed generation and a rural environment where visual and noise aspects need to be minimal. I'll follow with interest any ideas that come up in that respect.

Great video. Shows there are a lot of pitfalls in VAWTm design. I think they have great potential in urban areas without necessarily beating or matching HAWT efficiency...and I'd like to see the maths too

@sbok9481

Жыл бұрын

Just now, I did some basic calculations and used it to increase the VAWT efficiency by a whopping 43%. Such a simple solution.

I am also interested in the detailed design video with all the math :-)

I liked very much you quick introduction to the trhee-blade Darrieus VAWT. I love this turbine, as in the 90's I've analized this geometry for small hidrokynetic generation in Amazon basin. Since then it resides in my heart (I'm now working with small thermic machines to the same problem). Congratulations!

Surely the case for VAWTs should include their advantages at larger scale. This is the "elephants cannot jump" argument. As any structure is scaled up, stresses in that structure increase as the scale, so if you make something twice as big it has eight times the volume and eight times the mass, maybe eight times the cost, and gravitational bending stresses within the structure double. This is a problem for HAWTs, because this increase in stress applies to gravitational bending in the blade roots and this is a fatigue driver and hence a driver of cost of energy LCOE from HAWTs. VAWTS do not suffer this same cyclic fatigue stress and so were thought in the 1980s (when I did my PhD in VAWT aerodynamics) to be destined to replace HAWTs eventually when wind turbines reached large enough scale. (Aerodynamic stresses become less and less important with increased scale.) As it happens we are actually clever enough to make bigger things more expertly and so things including wind turbines do not increase in mass as the cube of linear dimension, but rather mass increases as scale to a power of about 2.2 to 2.6. Amusingly we might remember that body mass index (BMI) is calculated from mass/height^2, not height^3. The effect of this is that gravitational bending stresses do not increase as scale, but they still increase strongly. To combat these increases in stress we hear that more expensive materials (kevlar and carbon fibre) are increasingly used in modern turbines, perhaps to cope with this gravitational edgewise bending fatigue problem. Presumably there will come a time when it will be cost effective to switch to VAWTs?

@jazldazl9193

2 жыл бұрын

Can you enlighten as to which is the most efficient blade design of VAWTs so far please?

@ThrashLawPatentsAndTMs

2 жыл бұрын

@@jazldazl9193 @Colin Oram -- I would love to know your thoughts.

@gerald1455

2 жыл бұрын

study the 4 mw EOLE darelus that cost around $40 million

I would love to see a video detailing the basic mechanical needs and physics of a pitch controlled H-style VAWT. It would be interesting to see how complex it really needs to be. Loved the video!

@VacuousCat

Жыл бұрын

just search "cyclorotor"

Nicely done! One potential use for VAWTs, where there may be an improvement over utility-scale HAWTs, is for floating offshore wind. The lower center of gravity significantly reduces the size requirement for the floating platform, potentially reducing the cost of energy. Of course, fatigue is still an issue that must be addressed, and there are a few tricks up our sleeves that might help. The US DOE is funding a program (ATLANTIS) that it includes a VAWT design component.

Thank you for such a simple explanation of the aerodynamics for the VAWT. I now have a better understanding of the efficiencies for this turbine.

I live in north Texas with constant, powerful wind. I use VAWT exclusively, utilizing both Darrius as well as Savonius designs I have refined over the past 57 years. I am 74. My vawts have completely overcome flutter, stall, vibration, over-speeding problems as well as have zero electrical loading and unloading with wind speed and frequency changes, because one design utilizes 4 moving parts, while another utilizes 2 and ALL my birds compress air into an air grid for storage. Electricity is manufactured in my shop utilizing any of several air-driven engines of my own design. I have several air-driven appliances I have manufactured over the years. Edit: New Sub. I love physics!

Hi Rosie! Thank you so much for sharing your well-articulated and super informative videos here on KZread. You are a truly inspiring educator. I am a senior wind turbine control systems engineer in the U.S. and have recently been designing the control system and algorithms for a ~100kW H-type VAWT. The turbine has three straight fixed blades, all aluminum. There is no blade pitch mechanism. The lead turbine engineer wants to regulate power in high wind (region 3) via stall regulation by truncating rotor speed past a certain wind speed, thus stalling the blades to prevent increasing torque with increasing wind speed. However, this strategy will generate turbulent flow and potentially damaging vibrations that will lead to early fatigue of the blades and arm connections, as you so eloquently explain in your videos. It is also dicey trying to stall regulate in this fashion because the generator and electronic power converter equipment is required to have sufficient overdesign to handle the surge torque needed to decelerate the rotor in gusty wind in order to keep the rotor in stall. Any slop in the RPM regulation can cause a runaway condition whereby the rotor overspeeds to the point aerodynamic torque exceeds the electrical torque capability of the system, thus the rotor suddenly becomes impossible to decelerate without emergency brakes. The reliance on generator torque to stall the rotor also makes for poor power quality due to electrical torque fluctuations and surges. I have been trying to encourage the design team to consider a future blade pitching approach to simultaneously reduce stall-induced vibrations while also making speed regulation safer and more robust. I'm also concerned with their choice to use aluminum blades, as they will fail sooner, making for a poor quality product and disappointed investors. What are your thoughts? Are you available for consulting? Our company is based in Northern California and our current design prototype is located in the Texas panhandle and is nearly finished. We are commencing initial tests next week.

@EngineeringwithRosie

2 жыл бұрын

Hi! Thanks for this comment it is great to hear from someone working on a real-life VAWT project! Your concerns all seem very much in line with the experience of previous VAWT trials. Have you seen this Sandia report? It could help you communicate your concerns to your colleagues. energy.sandia.gov/wp-content/gallery/uploads/SAND2012-0304.pdf I am indeed available for consulting, you can get in touch through my company email rosemary (at) pardaloteconsulting.com

@tlangdon12

Жыл бұрын

I would share your concerns. A better arrangement to regulate power in high winds is to set the blade angle for as much anti-rotational torque as you can without stalling the blades (and then zero torque), but if you have no ability to change the pitch you are left with the electrical torque that the generator can produce, and as you observe, if this fails, you will get a runaway. To my mind any turbine needs an emergency brake, so it would be better to plan on implementing them from the outset.

Great video, Rosie. One thing I’d be interested to see is your thoughts and calculations on the clustering of VAWTs which I have heard increase their efficiency (unlike HAWTs which are disturbed by nearby turbines).

Hi Rosie. Our presentation is simply fantastic. Congratulations for presenting us with such an interesting and complex topic in a way that is so much easier to understand. Surely, this reflects all your professional competence. Thank you very much, and may God bless you. RVC - Brazil

Just subscribed.. a full video with all the calculations is very much appreciated. Thanks for your good work

- very informative video! I think the Voith Schneider propeller's active pitch control system would make a great system to be adapted for use on VAWTs with active pitch control. Both the direction and the amount of pitch are variable so it would allow efficient operation over a range of tip speed ratios. The system has been used for many years on tug boats and other work boats/ships. I would like your reaction to the VAWT of US Patent #9,494,136. All blades are interconnected forming a stiff structure.

@EngineeringwithRosie

3 жыл бұрын

Interesting, thanks! I will look into these topics.

This was interesting. More math and CFD would be great. Thanks.

Excellent video. One extra detail for those interested: aircraft wings are also tapered and twisted, for two reasons: 1) To reduce wing tip vortices (drag). 2) To make the outer parts of the wing stall later than the inner parts, to allow control to be maintained to get out of the stall.

Really love these videos, Rosie. Thanks for educating us all with your knowledge. I'd like to request a video where you analyze or suggest which regions of the US or of the world are best suited to harnessing wind energy, specifically residential wind energy. Or more generally how to set up a home/residential wind turbine so as to optimize power generation. i.e. how high off the ground to get sustained wind, optimal turbine size needed to generate n watts of power, the probability of having at least a critical threshold of power generated from that turbine as a function of latitude/longitude/elevation, etc. I would bet many viewers of these videos are doing so with the goal of setting up their own wind turbine to power their home in some sort of off-grid or grid-tie situation. As always, thanks and I appreciate your insights!

I looked into getting a residentially vertical axis windmill and was disappointed that there were so few providers and that I was told to not put it on the roof of my house due to vibrations. Now I understand why, thanks for that

@EngineeringwithRosie

3 жыл бұрын

I wish wind turbines were as easy to put on roofs as solar panels but unfortunately that's not how it works!

@g-r-a-e-m-e-

3 жыл бұрын

Also unlikely to generate significant power, with a tiny turbine.

@vremster

3 жыл бұрын

Check out Flower Turbines (flowerturbines.com/). They are a startup in Rotterdam, and will soon be producing turbines in the US, as well. They've patented a few breakthroughs in VAWT technology for residential and urban use.

Give us the math! Also, it would be great to talk about what makes an efficient generator, especially for slower speeds (e.g. low speed wind recovery with vertical axis turbines).

For some reason this got in my recommendations... I'm not really an engineer, more a designer. But I wish I had you as my teacher back in my college days!

Great content explaining of different design for vertical axis wind turbines.

I love that you add a math component to your video......

Great content! When talking about pitch variability in VAWTs, a helicopter swash plate comes to mind. The greatest loss in efficiency is likely scale, as the area comparison of presented cross wind between VAWT and HAWT just doesn't compare.

@tlangdon12

Жыл бұрын

Vertogen are working on just such a design.

Fascinating. Thank you!

Well done, Rosie. Thanks for the explanations. Compromise is usually best functionally. My 1st reaction is to place the complexity of function into the manufacturing process: for instance a helical design. Once the vawt is in place, if well-manufactured, the product should perform with little need for on-site adjustments and maintenance. This may be less optimal in energy generation than adjustable vanes/airfoils but better for long-term low maintenance.

The scientific answer is unequivocally yes... I spent over ten years as a wind generator turbine and Axial Flux Alternator Design Engineer for the American Energy Research Laboratory. I designed, fabricated and studied many VAWT designs in dynamic environments. VAWTs are uniquely interesting but cannot compete with HAWTs in power generation on physical dimension characteristics. My data indicated the the swept area of a VAWT must be in excess of 4X that of a HAWT to produce a similar output energy production. That was when compared to the most efficient designs available. As an example: A VAWT will require a physical size of +360 sqft swept area (10' X 36') turbine to produce the production of a 10 foot diameter HAWT with 81 sqft of swept area. Both turbines will produce "realistically" approximately 500-1000 watts. Advertisers of wind turbines routinely indicate 2X - 3X more production based upon non-standard values. If you are interested... You can also "guess" the useful output of a generator by weight. Since most "motors" are fabricated using the same components and materials I use a simple rule of thumb. 26 pounds of generator = 742 watts. Once again.... Advertisers claim much much more due to various methods of non-standard calculations. How do I know this? 11 additional years employed as an Engineering Technician for a major motor manufacturing company testing many different motor and generator designs and producing valid data to design engineers producing more efficient products.

@theosky7162

Жыл бұрын

Where do you recommend I look to compare retail generators suitable for VAWT diy? Thanks!

@mgold4685

Жыл бұрын

@@theosky7162 I do not recommend any VAWT. They are too inefficient for the investment. I recommend a small HAWT to supplement your solar system as part of a hybrid system design. I have attempted many VAWT designs new and old in research for efficiency. None exceeded the three blade common HAWT design. As stated earlier, It takes 4X the swept area of a HAWT to match its output capacity. Unless you are doing hobby research I would not bother. There are hundreds of examples of VAWT deployed designs shut down around the world... Buy a HAWT...

@theosky7162

Жыл бұрын

I get the efficiency problem of VAWTs as you have well explained. My question is directed at Generator sources or design class suggestions, as I noted your prior experience as an Alternator Design Engineer. Perhaps I'm still at the 'hobby research' stage, but my intent is to build a multi-input grid-tie system that supplies power to my home, manufacturing shop, and neighbors. As you are surely aware, technology in all the related fields is changing fast now. Solar panels, Battery storage, Wind Turbines, Capacitors, Transformers, Inverters, Hyperbolic collectors, etc... it's a deep dive on all. At the moment I'm concentrating on rotational to electric conversion. Any product compilations for capacity / cost / sources that you know of would be greatly appreciated.

@mgold4685

Жыл бұрын

@@theosky7162 I understand...First, let me explain my current build and strategy. I live NW of Amarillo outside any code restrictions. I live 100% off-grid. I have little knowledge of grid-tie systems. I designed, fabricated and distributed a couple of small wind generator APMA's. The designs were sound and extremely reliable but the overseas markets set the retail prices far too low to meet a standard business model. The company was American Energy Research. I sold all the fabrication equipment to Hurricane Wind Power several years ago. Now, the good part! I have built a solar/wind off-grid system to support a 20 acre location on a mesa far enough from Amarillo to not feel the "city" effects. I am still building, or expanding my system. Currently I have 60+ solar panels deployed and another 60 to be installed. These are 24v panels from 225W to 400W. I have upgraded my charge controller/inverter system from PowerJack and MpptSolar to MppSolar models 6048 & 6548 inverters. My system was 24V and upgraded to 48V. I still use GC-2 & GC-8 FLA batteries over 40 of them. I recently purchased (5) 5.2Kw EG-4 server style LiFePo battery packs for storage. Currently I only have one 400W 48V HAWT wind generator to "top-off" my battery storage system. As I mentioned earlier a "hybrid" system is needed in almost all applications. Let me know where your install will be and I can give you a rough idea of the "mix" required to design a working system. Wind is not an issue here as well as sun. I am willing to help you in your quest if I can

I'd love to hear your thoughts on so-called "solid state" wind turbines or if those are just far too new and unproven to have much data/theory on them.

I would really like to see a video with the heavy maths! Thanks for this video series, you gained a new subscriber.

Very nice video ! Usually so many people say anything about wind turbines, especially for VAWT ! To my point of view, the best compromise for a VAWT is a Darieus twisted mode (twisted for a more constant torque as you mentionned). I worked ten years ago of such project. It was so exiting to play with aera (and CFD), structure (FEM) and electrotech to control the speed (and the power). May be you should notice this point for VAWT. Without furling and pitch for twisted, regulation can just be done by a controler on the TSR (to reduce efficiency)

Like many other viewers, I would love to see those math equations Rosie. Also it would be nice if you can tell us about any typical software that is used for those calculus. Thx!!

Excellent content! Very able to understand and I am very rusty in the tech. Also a very joyous attitude and a killer smile. Able to easily tell you love your work!

Very helpful and informative. Thank you!

Have you seen the Powerpod? Promising or puff? Thank you for the informative video!

thanks for your efforts in wind energy, you are doing a good job, can you put more on Double Multiple Stream Tube with VAWT

@EngineeringwithRosie

3 жыл бұрын

I will try my best 😀 it's a big topic, so probably it won't come before the end of the year.

These videos are so excellent! I just subscribed, and I wish you many more subscribers to come!

Agree Rosie, I think we are heading for blended energy solutions dependant on the local ecosystem. Nice one Rosie.

Hi Rosie! I love your channel and what you’re doing with it. I accidentally put my comment as a reply to another comment, so it’s a bit buried now. I am interested in wind turbines for off grid applications for small cabins. I will likely install solar systems and the wind turbines will be supplemental to the PV panels. I have not done a formal wind study, but I looking into installing a weather monitoring station to start collecting data. I’ve live on the land for a year and that has shown me that we have gusty winds that are occasionally very strong. There is usually a slight breeze, but I would not classify the land as a high wind location. Thanks so much!! Tom

@EngineeringwithRosie

3 жыл бұрын

Thanks Tom, I found your buried comment already. And suggested that you measure wind speed so it seems you are way ahead of me there! Remember to take the wind speed where you want to put the turbine. Near to the ground it will vary a lot from one location to another even close by. Compare your data to published long term data to see how your long term values might look.

@TomTaberHODL

3 жыл бұрын

@@EngineeringwithRosie Thanks Rosie! I’ll get a weather station and see what I discover. Since I wrote that comment, I’ve been paying more attention to the wind and realize that it’s much stronger and more frequent than I realized. Thanks for responding! 🙏🏻

I did my fourth year engineering thesis on this back in 1975. I was limited by computing power.

@easternwoods4378

3 жыл бұрын

IBM 1130 4K punch cad input I found my copy of the thesis a few years ago and it sparked my interest again. I was simply looking at the torque curve vs the speed ratio. It will rotate to a point and then the torque goes negative so it won't increase in speed. If you add a motor assist to brig the speed ratio over 1 then the torque value continues to increase. That's as far as I got. I never had the computing power to model 3 blades ( or more ). Nor did I try to extract power. I've always wanted to know the limit Betz Law on vertical axis turbines. I've always assumed 3 blades to be the most effective simply because of the accumulation of the sin curves like three phase power but that's not valid. Are more narrow blades more effective than fewer wide blades? Is there an optimum diameter? I just used 3 airfoil designs.

@RobBCactive

3 жыл бұрын

@@easternwoods4378 Thanks for sharing this, it's fascinating to hear about

@easternwoods4378

3 жыл бұрын

@@RobBCactive All I was able to do was rotate the "wing" in relation to the central axis and then transit around the central axis to find the toque curve. Once you get over a speed ratio of one the wing has a velocity approaching the leading edge. It's the same a foiling in the America's cup down wind.

@RobBCactive

3 жыл бұрын

@@easternwoods4378 I have trouble seeing why it generates torque when the wings are rotating through 360⁰, I would expect it all to cancel out.

@easternwoods4378

2 жыл бұрын

@@RobBCactive What I did was rather rudimentary. At a low relative velocity the wing going upwind will have a relative velocity of v ( wind ) plus the rotational velocity. The wing going downwind is v ( wind ) minus the rotational velocity. In effect the wing has the trailing edge facing into the wind. In one rotation of the main axis the wing stalls several times. It effectively becomes just a barn door when the wing is perpendicular to the flow. When you get to a speed ratio higher than one then even on the down wind side the wing is seeing the airflow coming to the leading edge. It does however oscillate between a positive lift and negative lift. At low speed ratios it's basically an anemometer. At a speed ratio of one the torque is negative so it won't ever over speed on its own. Once you get to a speed ratio greater than one the torque output increases rapidly. the torque value vs speed ratio is an S curve. The "trick" is to find the optimum wing angle between the radius from the center point to the wing and then angle the wing. That's as far as I got. I never calculated the actual power output. It also means that you have to provide a power input to get to a speed ratio greater than one. It's hard to describe the the effect in words. I's a lot easier to draw a diagram.

Thanks Rosie. I really like and appreciate your videos.

Good on you Rosie. Thanks for he explanation of things I often wondered about

The whole way through I was thinking about changing the blade pitch, except using mechanical means. Probably not as good as doing electronically (as you could then adjust for wind speed as well as direction), but there are some relatively simple mechanisms that could be used at least to increase efficiency, even if it isn't quite maximised.

@jazldazl9193

2 жыл бұрын

Such as?

Hi there! Please do make this more detailed video :-)

I just stumbled on your videos. So glad I did. Very informative videos and interesting topics. I would really like to see the in depth analysis video you mentioned. Thanks for the video and information. Cheers

Excellent video...much much appreciated.

I think they could be on top of power poles in areas that get a good amount of wind.

The active blade pitch vertical wing could be achieved more simply on a flat wing with leading and/or trailing flaps / slats (similar to a jet's wing) rather than varying pitch on the whole wing. I think the wing could be made to fly at every point in its rotation by changing it from (relative) concave to convex.

@jenshobroh1294

Жыл бұрын

I would like to see more on that.

@tsbrownie

Жыл бұрын

@@jenshobroh1294 Someone else did it with mechanics, but I think the trend now is to use spiraled blades and more exotic shapes.

Hyee, just watched the whole video and I really love the way you delivering the knowledge. As my Final Year Project (some kind of research) is related with vertical axis turbine, this video is really helpful in the process of my understanding about this turbine.

Fantastic subject!! Are you ready for more?? Okay, let’s go. Of course I think that VAWT have so many benefits! Coming from Holland and specialized in energy gives near endless options if you live in Canada. Worked with hydraulic windmills horizontally, was in projects to tweak blades. But over all noice and high maintenance on bearings was cause for windmills to be out of service and expensive to maintain. Combined with space (minimal space required for VAWT), noise and added consequences make me aim for vertical. Yes, I see this as best for our future worldwide but we have some development to go through! Welcome in the miracle world, you bring us the future!!

Can we please get the in depth video on VAWT design? Great video but I was expecting much more detail

Can you recommend a commercial DIY kit? I have wanted to play with one as a hobby for a long time.

I have studied vertical axis turbines and came to the exact same conclusion as you: variable pitch is the answer. The efficiency is so much better. But I needed also to acknowledge: nothing for small, home scale turbines because of the explosive costs.

Brilliantly explained!

What do you think of Icewind turbines? I've been trying to figure out if any vertical design would work in the weak air pressure of Mars,

@flycastinginstrn

3 жыл бұрын

+1

@EngineeringwithRosie

3 жыл бұрын

Thanks for the suggestion, I'll add Icewind to my list for future videos. The power in wind depends on wind speed, V, and air density, rho: P=0.5*rho*V^3*A NASA gives data on the Martian atmosphere here: nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.html It seems wind speeds are a little lower on Mars than on Earth, but not so low you couldn't use an Earth-designed wind turbine there. A bigger problem is that air density is much lower, only 0.020 kg/m3 compared to 1.225 kg/m3 at sea level on Earth. So there is only one sixtieth of the power available in Martian wind compared to Earth wind (at the same speed).That means you would need a wind turbine sixty times as large to get the same power, and even then you would get less power out of it on Mars than you would on Earth due to the lower average wind speeds. I don't see any reason why you couldn't get a VAWT or HAWT to work on Mars, but it wouldn't be very effective compared to what we're used to on Earth.

@EveryoneWhoUsesThisTV

3 жыл бұрын

@@EngineeringwithRosie Thanks for the reply and data! :) I'm interested in Martian wind power, because every so often a big martian dust storm blows along and cuts off the light for solar. Possibly lasting for weeks. Having a way to keep batteries topped up (using the power of the storm) could be a life saver.. Am I right in thinking that the reduced density/power of the Martian air would make more light-weight turbines viable? Turbines too fragile to last here on earth, could perhaps be mounted on solar arrays to provide a secondary power source. I was picturing something like the Icewind turbine, made from thin aluminium and/or carbon fibre. Apparently, the Icewind's claim to fame is it's ability to operate in light winds. It's not the easiest thing to test at the moment as I'm between spacecraft just now. But I think wind power is being overlooked as a backup power source for a Mars base because of the low air density... Anyway, thanks for the info and all the data driven youtube vids...

@EngineeringwithRosie

3 жыл бұрын

Lower wind speed or lower air density does give so smaller forces, but also a corresponding lower power production. So unfortunately you wouldn't see any reduction in the weight of a Martian wind turbine compared to one on earth that produced the same power, except with respect to gravity loads (self weight). I guess your fatigue loads for a horizontal axis turbine at least would be lower, so perhaps you'd save some weight because of that but not a lot.

@D_Rogers

3 жыл бұрын

Well given the success of Ingenuity, and its flights I'm going to consider wind turbine power on Mars as a definite maybe! It seems to show more promise as we learn more, so I'm keeping it on my list of candidates

Maybe you have made this video already but, I would like to see a use case analysis for a vertical wind turbine. Like, say a single family home wanted to install one; how much would it cost and when would the return on investment be?

@tzenophile

3 жыл бұрын

It would most likely break down before return on investment. And a family home would never get enough power to make any useful difference. Just get solar instead. There is a reason why VAWTs are not used, and the companies that 'reinvent' them go out of business, 100 years after Savonius invented them. You'd think 100 years would be enough for optimization.

@moatplay

3 жыл бұрын

@@tzenophile That would be part of the assessment. Mean time between failures or MTBF. It is another metric we can measure.

@tzenophile

3 жыл бұрын

@@moatplay An honest company would give you that. And you'd see that the sum would be negative.

@jazldazl9193

2 жыл бұрын

@@tzenophile is it enough for optimists?

@tzenophile

2 жыл бұрын

@@jazldazl9193 100 years? Do you know the definition of insanity? "Doing the same thing over and over again and expecting a different result."

Great video, very informative. Thanks.

I loved this piece and have pointed some of our customer at it. We make the Darrius helical turbine you refer to in the video. If ever you want to chat happy to talk.

HI Rosie, greetings from Colombia. I wonder what is your opinion on ART wind turbines? Is ot worth the trouble? Thanks for your job in communicating this extraordinary world of wind power!

@EngineeringwithRosie

3 жыл бұрын

Hi Camilo, thanks for you comment. I don't know ART turbines, and I am just getting hits for paintings of wind turbines when I Google it! Can you share a link so I understand what you mean? Then I will add them to the list for a future video to look in depth at some VAWT designs.

@KnotRight4Ever

2 жыл бұрын

@@EngineeringwithRosie commenting to hear his response, also instead of complexing the mechanics by rotating the blades to solve the negative force area couldn't u just use a one way filter membrane to allow force in the positive direction of the wind and pass-through of wind in the negative force area or u could go more complicated and use a full spherical gyroscope design like nasa uses to test astronauts in a zero spin scenario. Then in the negative area the blades would move up an down cutting the negative wind area space by half and creating a more stable center of gravity under the wind force. I wish I had the means to test both and both together but I don't so I'm just passing along my thoughts 🤔👍

I think the helical turbines look pretty good, almost like some art installation. If I wanted one I'd probably choose one of those.

@GoatZilla

3 жыл бұрын

Solid engineering mindset on this one.

Very informative, thank you

I enjoyed your video. Thank you.

Hello Rosie, very nice video. I now have a good understanding to what to design for while developing my own VAWT. Can you make a video on which type of airfoil (a lot of different designs available out there) is suitable for developing a 3/4 blade Helical-VAWT. Thanks and Regards.

@danedmiston9673

3 жыл бұрын

Here is an airfoil designed for VAWTs. airfoiltools.com/airfoil/details?airfoil=du06-w-200-dt It is very important to scroll down to the Cl/Cl v Alpha graph. The angle of attack is the X axis and the Lift to Drag ratio is the Y axis. The colored lines represent the Reynold number the airfoil is operating at, effected by the speed and the chord (width) of the airfoil. There is a Reynolds number calculator in the top left corner in the Applications section. Based on the graph, a 1.5 meter wide airfoil operating at 10 meters/second would work very well. A 100 mm wide airfoil operating at 5 m/s would be worse than terrible. The characteristic of airfoils to perform poorly at low Reynolds numbers is why small, lift type, VAWTs are not popular.

@EngineeringwithRosie

3 жыл бұрын

Great question, great answer! I will include information on airfoils when I make a video on detail design.

"Just Have A Think" talked about putting VAWT's in the center margins of busy highways to capture the "waste energy" from passing cars. That would seem to fit the definition of a turbulent flow (opposing flow?) and might help with overall efficiency. The space is usually unused, and any power generated could be used to power roadway lights at night. kzread.info/dash/bejne/mZeH0NmQZdmZlps.html

Excellent. Thank you.

My take on the VAWTs is that they tend not to chew up a lot of real estate, so, might be more practical for off-grid applications, especially if you need to run multiple turbines due to relatively low efficiencies. I am not an engineer, but I tend to see things from an engineer's point of view. I would like to see a multiple turbine setup using the helical blade design. Another thing that wasn't addressed is the lowest windspeed for practical generation. I envision a hybrid setup with solar as the primary, and wind as the night time/cloudy day backup. Sorry, I have rambled. You gave me a lot to think about, thank you

Rosie, you clearly have a beautiful mind and such a joyful demeanor. Thanks for sharing your knowledge and cheer 🙂.

Amazing explanation, liked and subscribed!

thank you for this wonderful video

maths for sure! Would love to see the mathematics behind these turbines. Maybe a numerical model? That'd be mint. Also, I got here via Just have a think. Glad Dave gave you a shout, great channel!

Thanks. Very detailed but useful.

Thank you so much for this. I really think VWAT have a place in the green energy we need. A fixed variable pitched turbine ( lower cost as opposed to mechanical moving blades)would be easy to incorporate into a small system for home generation, with a much smaller footprint of a HWAT. Easier to install and maintain.

Thank you Rosie for introducing VAT

I do think VAWT has its own niche and should not try to compete with HAWT in terms of efficiency. However, we do need to find a way to improve its efficiency as much as we can while still maintaining its advantage over HAWT (omnidirectionality, lower cut-in speed, simpler design, etc). As you have mention in the video, for a distributed, off grid, remote area, and site with lower average wind speed, VAWT is the better choice over HAWT. Finally, i loved your channel and i am glad it popped up in my recommendation algorithm ! Cheers from southeast asia !

Thank you, Rosie, I Love your work and great effort❤ Greetings from Egypt 👋

Yes, ! I WANT ALL aerodynamics of vwat! Greetings FROM México

I watched this again in December 2021 and note that a paper was published this month which became available as a preprint about the time you published this presentation. It is based on thesis research by Joachim Hansen under the direction of Dr. Iakovos Tzanakis. What makes it interesting is the analysis of the collective effects of “farms” of VAWTs, with spacing and rotation direction as additional design elements. The citation is Renewable Energy, 2021, vol. 171, issue C, 1371-1381. It may be downloaded at no cost.

Valuable information. I have always wanted to believe that vertical and helical turbine would be the most efficient. Clearly there is much more to the physics and implication for blade design than I thought. I would appreciate more discussion of the pitfalls of vertical design. We have solar panels and regular winds and have imagined a supplemental wind contribution. I really do not understand the losses to friction and component stressors in horizontal and vertical systems and would love a discussion and comparison of these isssues.

I think you're great. Smart, knowledgeable, friendly, accessible and on a topic I like a lot. I have a small item of feedback which I hope you find helpful and not hurtful. The smile seems forced or scripted and has seemed out-of-place to me since day one. Thanks again for some fantastic videos.

Thanks Rosie for the Maths Explaining the Wing/Blade Forces for a VAWT. Interesting.

I did a rudimentary vertical axis turbine to pump water for a small village using three sails...like the triangular sails in larger fishing boats. The sails adjust when facing the wind directly as well as when it faces the negative force. It however does need a bit of play on the sail's horizontal beam.

@EngineeringwithRosie

2 жыл бұрын

That sounds really cool!

I swear you made this so much easier to understand than my college professors. Thank you so much you are great

I have, over the past 50+ years, overcome ALL of the design limitations of my VAWTs. I use a flat, symmetrical-section vertical "H" design started with a small Savonius rotor at the center. My largest vawt swings a 10-foot arc. I deal with efficiency down on the ground by tweaking how I use the constant energy supply provided by my several turbines. ALL my turbines compress air, and I utilize that stored (in air receivers) potential energy against pistons or pelton-wheel turbines down on the ground, safely inside my shop. I'm 74 years old, and ALL my VAWT towers are counter-balanced, so they fold down easily with just one hand. My tallest turbines are 20 feet tall. I am working towards having 30 VAWTs all compressing air. I store at 120 psig and use automatic condensate drains and check valves on all receivers. I haven't had any mishaps yet and it's been going on 60 years since I started.

I lean towards the vertical axis turbine, no pun intended,lol, I like the variable pitch idea and can see the added complexity with moving parts etc, I wonder if spring loaded blades could be effective . .. Thanks Rosie!

want that video you mentiones with all the math and details, we all here are nerds for math and info! :D Love your work and videos!

i am exploring vawt as a solution to a specific challenge on my sailboat. Small, quiet, doesn't have to be efficient - just consistent.