But that's not squaring the energy produced. That's just squaring the area of wind interception.Rum wrote: ↑Fri Jun 15, 2018 9:04 pmBasic geometry from Form 3. Of course I knew that..but kind of forgot it...*cough*Brian Peacock wrote: ↑Fri Jun 15, 2018 8:52 pmThe effective area of a wind turbine is the circle described by the radius of it's blades.
The effective area of the 20m turbine is 1256.64/314.16 = 4 times greater than that of the 10m turbine.
- Area of a circle = πr2
10m radius: A = 314.16m2
20m radius: A = 1256.64m2
Another maffs thing I don't unnerstand
- pErvinalia
- On the good stuff
- Posts: 59393
- Joined: Tue Feb 23, 2010 11:08 pm
- About me: Spelling 'were' 'where'
- Location: dystopia
- Contact:
Re: Another maffs thing I don't unnerstand
Sent from my penis using wankertalk.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
- Brian Peacock
- Tipping cows since 1946
- Posts: 38061
- Joined: Thu Mar 05, 2009 11:44 am
- About me: Ablate me:
- Location: Location: Location:
- Contact:
Re: Another maffs thing I don't unnerstand
See JimC's answer above.
Rationalia relies on voluntary donations. There is no obligation of course, but if you value this place and want to see it continue please consider making a small donation towards the forum's running costs.
Details on how to do that can be found here.
.
"It isn't necessary to imagine the world ending in fire or ice.
There are two other possibilities: one is paperwork, and the other is nostalgia."
Frank Zappa
"This is how humanity ends; bickering over the irrelevant."
Clinton Huxley » 21 Jun 2012 » 14:10:36 GMT
.
Details on how to do that can be found here.
.
"It isn't necessary to imagine the world ending in fire or ice.
There are two other possibilities: one is paperwork, and the other is nostalgia."
Frank Zappa
"This is how humanity ends; bickering over the irrelevant."
Clinton Huxley » 21 Jun 2012 » 14:10:36 GMT
- pErvinalia
- On the good stuff
- Posts: 59393
- Joined: Tue Feb 23, 2010 11:08 pm
- About me: Spelling 'were' 'where'
- Location: dystopia
- Contact:
Re: Another maffs thing I don't unnerstand
See my answer above that. That will only square the energy produced in a frictionless and weightless environment. I.e. doubling the length of turbine blades doesn't square the energy produced.
Sent from my penis using wankertalk.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
- pErvinalia
- On the good stuff
- Posts: 59393
- Joined: Tue Feb 23, 2010 11:08 pm
- About me: Spelling 'were' 'where'
- Location: dystopia
- Contact:
Re: Another maffs thing I don't unnerstand
You know, you are becoming a real pain in the arse. And you know how I treat people like that. Is this really where you want to go?
Sent from my penis using wankertalk.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
- JimC
- The sentimental bloke
- Posts: 73119
- Joined: Thu Feb 26, 2009 7:58 am
- About me: To be serious about gin requires years of dedicated research.
- Location: Melbourne, Australia
- Contact:
Re: Another maffs thing I don't unnerstand
It will be a pretty good approximation, given that modern turbines have magnetic bearings with very little friction...pErvinalia wrote: ↑Sat Jun 16, 2018 12:41 amSee my answer above that. That will only square the energy produced in a frictionless and weightless environment. I.e. doubling the length of turbine blades doesn't square the energy produced.
Another vital factor is the height of the swept area above ground - the higher the better, given the ground turbulence effect...
Nurse, where the fuck's my cardigan?
And my gin!
And my gin!
- pErvinalia
- On the good stuff
- Posts: 59393
- Joined: Tue Feb 23, 2010 11:08 pm
- About me: Spelling 'were' 'where'
- Location: dystopia
- Contact:
Re: Another maffs thing I don't unnerstand
I'm sorry, but no. If this gave a good approximation in the real world, we'd have turbines hundreds of metres tall. We don't, because the gains become incremental due to losses from increasing weight and increasing friction. And friction isn't just in the bearings. It's also as the blade cuts through the air.
Sent from my penis using wankertalk.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
- JimC
- The sentimental bloke
- Posts: 73119
- Joined: Thu Feb 26, 2009 7:58 am
- About me: To be serious about gin requires years of dedicated research.
- Location: Melbourne, Australia
- Contact:
Re: Another maffs thing I don't unnerstand
Actually, we do have turbines that have a hub height of around 180 metres, and with the tip of the blades reaching to 250 metres. The fact that there will be limits on turbines beyond a certain size has nothing to do with a very clear and exact relationship between power and the square of blade length. There are several reasons why going much bigger than the biggest current turbines would not be sensible, but friction is not the issue (both air and magnetic bearing friction is small compared to the propulsive force of the air, and would increase only in a linear fashion in any case). The limitations on size are largely problems of strength, weight and rigidity, plus the engineering difficulties of manufacture and erecting such giants. You would reach a point where it is more economical to have 4 of the current giants rather than 1 super giant producing the same power as the 4.pErvinalia wrote: ↑Sat Jun 16, 2018 1:57 amI'm sorry, but no. If this gave a good approximation in the real world, we'd have turbines hundreds of metres tall. We don't, because the gains become incremental due to losses from increasing weight and increasing friction. And friction isn't just in the bearings. It's also as the blade cuts through the air.
Nurse, where the fuck's my cardigan?
And my gin!
And my gin!
- pErvinalia
- On the good stuff
- Posts: 59393
- Joined: Tue Feb 23, 2010 11:08 pm
- About me: Spelling 'were' 'where'
- Location: dystopia
- Contact:
Re: Another maffs thing I don't unnerstand
The difficulties are what I and Svarty are talking about. So it's wrong to claim a wind turbine will output the square of its power when it doubles in prop length. A theoretical turbine would, but in the real world, no.
Sent from my penis using wankertalk.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
"The Western world is fucking awesome because of mostly white men" - DaveDodo007.
"Socialized medicine is just exactly as morally defensible as gassing and cooking Jews" - Seth. Yes, he really did say that..
"Seth you are a boon to this community" - Cunt.
"I am seriously thinking of going on a spree killing" - Svartalf.
- JimC
- The sentimental bloke
- Posts: 73119
- Joined: Thu Feb 26, 2009 7:58 am
- About me: To be serious about gin requires years of dedicated research.
- Location: Melbourne, Australia
- Contact:
Re: Another maffs thing I don't unnerstand
Well before those real-world difficulties emerge (when going beyond the current giants I mentioned), the relationship would in fact hold. A blade length of 4 metres would produce 4 times the power of a 2 metre blade.pErvinalia wrote: ↑Sat Jun 16, 2018 4:29 amThe difficulties are what I and Svarty are talking about. So it's wrong to claim a wind turbine will output the square of its power when it doubles in prop length. A theoretical turbine would, but in the real world, no.
Nurse, where the fuck's my cardigan?
And my gin!
And my gin!
- Rum
- Absent Minded Processor
- Posts: 37285
- Joined: Wed Mar 11, 2009 9:25 pm
- Location: South of the border..though not down Mexico way..
- Contact:
Re: Another maffs thing I don't unnerstand
They said it in Youtube so it must be true. Plus Jim is a maffs god!
- Scot Dutchy
- Posts: 19000
- Joined: Tue Feb 23, 2010 2:07 pm
- About me: Dijkbeschermer
- Location: 's-Gravenhage, Nederland
- Contact:
Re: Another maffs thing I don't unnerstand
There is a thing called "moment" (the air speed needed to turn the blades). Different designs have different moments . The shape of the blade has a great influence on the moment. The ones with the smallest moment cant handle strong winds and have to be feathered to avoid damage. The ones with the biggest moment can handle very strong winds but need mechanical help to get moving.
The mount of power produced is not just dependent on size but on design.
The mount of power produced is not just dependent on size but on design.
"Wat is het een gezellig boel hier".
- Rum
- Absent Minded Processor
- Posts: 37285
- Joined: Wed Mar 11, 2009 9:25 pm
- Location: South of the border..though not down Mexico way..
- Contact:
Re: Another maffs thing I don't unnerstand
I'm sure that is a factor but the OP was about the relationship between blade length and energy production and for me at any rate the odd thing that it is so proportional.
- Scot Dutchy
- Posts: 19000
- Joined: Tue Feb 23, 2010 2:07 pm
- About me: Dijkbeschermer
- Location: 's-Gravenhage, Nederland
- Contact:
Re: Another maffs thing I don't unnerstand
Blade length is not the story but design is.
Wind Turbine Blade Design, Flat or Curved
Wind turbine design: Building a better blade
"Wat is het een gezellig boel hier".
- Rum
- Absent Minded Processor
- Posts: 37285
- Joined: Wed Mar 11, 2009 9:25 pm
- Location: South of the border..though not down Mexico way..
- Contact:
Re: Another maffs thing I don't unnerstand
No. The story is blade length. That is what the OP says.Scot Dutchy wrote: ↑Sat Jun 16, 2018 8:12 amBlade length is not the story but design is.
Wind Turbine Blade Design, Flat or Curved
Wind turbine design: Building a better blade
- Scot Dutchy
- Posts: 19000
- Joined: Tue Feb 23, 2010 2:07 pm
- About me: Dijkbeschermer
- Location: 's-Gravenhage, Nederland
- Contact:
Re: Another maffs thing I don't unnerstand
Nope design or cant you see that. What sort of blade? Shape and thickness is far more important. No blade is a simple blade.
"Wat is het een gezellig boel hier".
Who is online
Users browsing this forum: No registered users and 14 guests