Messages in AirborneWindEnergy group.                           AWES27962to27998
 Page 9 of 9.
Group: AirborneWindEnergy Message: 27962 From: dave santos Date: 7/28/2019
Subject: Re: Musical AWE

Group: AirborneWindEnergy Message: 27963 From: dougselsam Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27964 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27965 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27966 From: joe_f_90032 Date: 7/28/2019
Subject: A specific AWES changes continuously.

Group: AirborneWindEnergy Message: 27967 From: joe_f_90032 Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27968 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27969 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27970 From: Joe Faust Date: 7/28/2019
Subject: A specific AWES changes continuously.

Group: AirborneWindEnergy Message: 27971 From: dougselsam Date: 7/28/2019
Subject: Re: Musical AWE

Group: AirborneWindEnergy Message: 27972 From: dougselsam Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27973 From: dougselsam Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.

Group: AirborneWindEnergy Message: 27974 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27975 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27976 From: joe_f_90032 Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.

Group: AirborneWindEnergy Message: 27977 From: dave santos Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.

Group: AirborneWindEnergy Message: 27978 From: dave santos Date: 7/28/2019
Subject: Re: Musical AWE

Group: AirborneWindEnergy Message: 27979 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27980 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27981 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27982 From: joe_f_90032 Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27983 From: dave santos Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27984 From: dave santos Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27985 From: gordon_sp Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Group: AirborneWindEnergy Message: 27986 From: dave santos Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Group: AirborneWindEnergy Message: 27987 From: gordon_sp Date: 7/29/2019
Subject: Re: Line Gallop and Strum (review and ST shaft context)

Group: AirborneWindEnergy Message: 27988 From: gordon_sp Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Group: AirborneWindEnergy Message: 27989 From: dave santos Date: 7/29/2019
Subject: Re: Line Gallop and Strum (review and ST shaft context)

Group: AirborneWindEnergy Message: 27990 From: dave santos Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Group: AirborneWindEnergy Message: 27991 From: benhaiemp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27992 From: dave santos Date: 7/29/2019
Subject: kPower's current testing

Group: AirborneWindEnergy Message: 27993 From: benhaiemp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27994 From: Peter Sharp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27995 From: benhaiemp Date: 7/30/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27996 From: benhaiemp Date: 7/30/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27997 From: benhaiemp Date: 7/30/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Group: AirborneWindEnergy Message: 27998 From: joe_f_90032 Date: 7/30/2019
Subject: Gábor Rudas



Group: AirborneWindEnergy Message: 27962 From: dave santos Date: 7/28/2019
Subject: Re: Musical AWE
Pierre, Music is just as closely connected to other technical fields as AWE. That's why you are here.

We have you and AWEfest as natural performance cases, plus all the common phonon physics, as well as the ancient traditions of musical kites.

There is no lie in stating AWE is quite musical in nature.



 

"which other technical conferences decline" is a lie.
Who tells this words lies.
Group: AirborneWindEnergy Message: 27963 From: dougselsam Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Peter:
The Reynolds number is kinetic effects / viscosity effects, meaning a low reynolds number indicates more fluid  "stickiness", which is why you find insect wings do not have airfoils because at that size, there is more proportional "stickiness" (like trying to swim in molasses(?)).  Basically it says below a certain size, standard airfoil shapes do not even work, and as you go bigger and bigger, airfoils get more and more efficient in providing "lift".

When you say "Maybe I’m missing something important."
Here's what I'm thinking you guys MAY be missing:

Magnus effect would seem to be more of a curiosity than a good tool, since it's been tried in wings and sailboats, but found lacking in both cases, or at least has not found a consistent use yet. 

If we want to do effective engineering, we should be using proven good components, rather than marginal components that consistently prove to be not so great.  Make sense?

I think part of "The Professor Crackpot Syndrome" is to confuse things that seem scientifically surprising or unexpected, with things that are effective and useful.  It goes into confusing effective inventing of useful things with demonstrating and incorporating things that are merely "unexpected" or "intellectually-interesting".

The dynamic would seem to be something like this:
Professor Crackpot wishes to demonstrate that he is "smarter than the average bear".
Meaning he can come up with something other people didn't think of, that is "better".
The fact that an effect merely exists does not automatically make it more useful for a given purpose.

But the good professor is a bit unorganized and impulsive, so he confuses the idea of incorporating something most people don't know about, with smartly coming up with a better way to do something. 

Unfortunately, the good professor is confusing "novelty" or "being different" with "superiority", which is why he is always drawn to vertical-axis turbines, magnus effect, etc., and always being proven wrong. 

Summary: "different" is not automatically "better".

Next chapter:
Why "Profethor Crackpot thta-thta-thtammerth and thpitth when he talkth and hath dandruff-encruthted glatheth  (Just kidding - that's mostly the cartoon version)

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Hi PierreB,

I read through the paper quickly. I don’t yet grasp the meaning of much of it due to my not having much experience with Reynolds numbers, so I can’t translate their findings into a practical prescription. I was surprised that the required power increased by the cube of the RPM. And I was surprised how much power was required to just spin a cylinder. That concerns me.

The lift coefficient data seemed to be in general agreement with previous studies, so I’m not yet sure if this study found something useful.

What do you find most interesting about this research, and about the lift coefficient? Maybe I’m missing something important.

PeterS

 

From: AirborneWindEnergy@yahoogroups.com [mailto:AirborneWindEnergy@yahoogroups.com]
Sent: Sunday, July 28, 2019 6:49 AM
To: AirborneWindEnergy@yahoogroups.com
Subject: RE: [AWES] The power consumption as the Magnus Effect Balloon or the Sharp rotor scales up

 

 

Hi PeterS,

 

I would like to read your comments about the paper I attached in my previous post, and I put again: https://www.sciencedirect.com/science/article/pii/S0167610518307396, particularly 3.1 : lift coefficient. Thanks.

 

PierreB

 
Group: AirborneWindEnergy Message: 27964 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Doug,


I take the Magnus balloon as an important AWE possibility not because it is "original", "new-style", "different", "crackpoted", but because a huge inflatable cylinder is easy to build, and could provide much lift in an almost stationary position. And PeterS has some experience about it. So I try to know more about it.
Group: AirborneWindEnergy Message: 27965 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
And also Doug,

Sails work for boats, but not for wind turbines. Bladed-rotors work for wind turbines, but not as sails. So it is not impossible a Magnus cylinder could work for only one thing. And if this thing was AWE?
Group: AirborneWindEnergy Message: 27966 From: joe_f_90032 Date: 7/28/2019
Subject: A specific AWES changes continuously.

A specific AWES changes continuously.

==============================

In the fine, any AWES changes continuously whether flying  or resting. 

Therefore, an AWES is distinct from its former self.  Some of the changing may lead to a failure of the machine to function; at failure, noticing that the AWES has changed may be starkly easier to identify.  Monitoring changes cannot ever be complete without God-vision; but sensors may trace selected parameters of an AWES while leaving some parameters unmonitored. Skill in selecting parameters to monitor may win profit competitions among competing AWES. And humans unable to be absolutely comprehensive in monitoring capacity, have the challenge of making selections of what to monitor. 
Group: AirborneWindEnergy Message: 27967 From: joe_f_90032 Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Group: AirborneWindEnergy Message: 27968 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Re (Reynolds Number) is not "stickiness" as such (not all viscous fluids are sticky) but the ratio of viscous to intertial forces, nor is higher Re better for flight, its often quite limiting, like in high Re kiteplane design.

Stokes worked Re out over 150yrs ago. Its expected of every aerospace student to grasp Re fundamentals in the first semester, and never stop learning the complex implications. Low Re is rather cool once you know its special wonders.

Reynolds number






 

And also Doug,


Sails work for boats, but not for wind turbines. Bladed-rotors work for wind turbines, but not as sails. So it is not impossible a Magnus cylinder could work for only one thing. And if this thing was AWE?
Group: AirborneWindEnergy Message: 27969 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Point of Fact: Sails have worked far longer for wind turbines than rigid blades, so lets agree they work.



Re (Reynolds Number) is not "stickiness" as such (not all viscous fluids are sticky) but the ratio of viscous to intertial forces, nor is higher Re better for flight, its often quite limiting, like in high Re kiteplane design.

Stokes worked Re out over 150yrs ago. Its expected of every aerospace student to grasp Re fundamentals in the first semester, and never stop learning the complex implications. Low Re is rather cool once you know its special wonders.

Reynolds number




On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎02‎:‎27‎:‎57‎ ‎PM‎ ‎CDT, pierre-benhaiem@orange.fr [AirborneWindEnergy] <AirborneWindEnergy@yahoogroups.com


 

And also Doug,


Sails work for boats, but not for wind turbines. Bladed-rotors work for wind turbines, but not as sails. So it is not impossible a Magnus cylinder could work for only one thing. And if this thing was AWE?
Group: AirborneWindEnergy Message: 27970 From: Joe Faust Date: 7/28/2019
Subject: A specific AWES changes continuously.

A specific AWES changes continuously.

==============================

In the fine, any AWES changes continuously whether flying  or resting. 

Therefore, an AWES is distinct from its former self.  Some of the changing may lead to a failure of the machine to function; at failure, noticing that the AWES has changed may be starkly easier to identify.  Monitoring changes cannot ever be complete without God-vision; but sensors may trace selected parameters of an AWES while leaving some parameters unmonitored. Skill in selecting parameters to monitor may win profit competitions among competing AWES. And humans unable to be absolutely comprehensive in monitoring capacity, have the challenge of making selections of what to monitor. 
Group: AirborneWindEnergy Message: 27971 From: dougselsam Date: 7/28/2019
Subject: Re: Musical AWE
daveS: The problem both you and JoeF are having is a lack of focus.  One day it's "Einstein", the next "music" - as though anyone cares about these endless excuses for nothingness.
Sure, anything and everything might somehow be relevant, but you two act as though there is no valid information to actually go on, hoping to somehow "just get lucky" with your aimless meanderings.  You protest my characterization of your approach as "monkey at the typewriter" but continue to divert your attention to every topic under the sun, never developing an AWE system of any kind..  What about "baking cookies"?  Doesn't "baking cookies" have SOME POSSIBLE relation to AWE at some level?  Why not spend a few weeks examining every conceivable aspect of "baking cookies"?  OK now I'm wanting to have a cookie.

You keep saying "power-kites" are "the answer".  You named your effort "k-power" where the "k" stands for "kite", so what we keep asking you is to show us how to use a power kite to generate electricity.  You seem to have endless excuses.  Your two latest are
1) safety so that even 10 kW is dangerous
2) copying my excuse that I am currently too busy with other crap (In my case, including REAL wind energy in a BIG way)
I would say, reason two I can obviously understand but you keep saying you are doing research but you still never come up with anything.  As for reason 1, try starting with kites small enough to be limited in danger potential.  Besides, smaller is cheaper and more achievable.  Get something working that is making any power whatsoever THEN
a) improve the performance and
b) increase the size as you see fit as you progress.
At least get something workable working at some level.
Unless you want to spend the rest of your life just repeating that flying kites or taking a nap "is" AWE.
If that's what you think, why bother even pretending to be involved with actual AWE?


---In AirborneWindEnergy@yahoogroups.com, <santos137@...  

"which other technical conferences decline" is a lie.
Who tells this words lies.
Group: AirborneWindEnergy Message: 27972 From: dougselsam Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Well I get what you are saying.  I understand what you mean.  I just think it seems unlikely.
If you want to tighten a bolt, for example, the standard tool is a wrench.  Doesn't matter if the bolt is for a ship, a bridge, an airplane, or a wind turbine, the tool that works best is a wrench of some type.  Now you COULD use pliers, but they would not work quite as well as a wrench.  So using pliers to tighten  bolt is like a vertical-axis wind turbine - it works, but you would be better off with a regular turbine.  You could also squeeze two wooden sticks between your fingers of both hands and tighten a bolt, but that would be more like a magnus cylinder - barely workable. 
Does a magnus rotor work better than an airfoil, wing, or kite for lift? 
Does a magnus rotor somehow work better than a wind turbine rotor for extracting power from the wind? 
What is the point?
I think what you guys need to do is hang an Easy-Bake Oven from a magnus rotor and call it a day.
Now watch JoeF and daveS spend the next week talking up Easy-Bake Ovens...


---In AirborneWindEnergy@yahoogroups.com, <pierre-benhaiem@...
Group: AirborneWindEnergy Message: 27973 From: dougselsam Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.
I favor a system where the only thing to monitor is power output, if possible.  K.I.S.S.


---In AirborneWindEnergy@yahoogroups.com, <joefaust333@...
Group: AirborneWindEnergy Message: 27974 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
"Does a magnus rotor somehow work better than a wind turbine rotor for extracting power from the wind?"
No, a Magnus rotor can provide lift and probably scale better.
For an AWE we will never have a wind turbine as efficient as a current ground-based wind turbine, but the space used is far larger. 
Group: AirborneWindEnergy Message: 27975 From: benhaiemp Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period.
Group: AirborneWindEnergy Message: 27976 From: joe_f_90032 Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.
Tortoise and Hare
T: Has some extra sensors on critical parts.
H: Has only power meter.
=====================================
Group: AirborneWindEnergy Message: 27977 From: dave santos Date: 7/28/2019
Subject: Re: A specific AWES changes continuously.
True, the AWES itself is always changing and that would be part of the complex mix of state variables. Classical physics is neither suited nor as explanatory as QM to deal with such subtle states.

Doug is out of luck favoring "a system where the only thing to monitor is power output". AWE is aviation, and there is rather more than power to keep track of for safe effective flight.

At least kPower knows to test max electrical load power by briefly shorting its generators, as the ultimate KIS kite power test, while also solving flight challenges.



 

A specific AWES changes continuously.

==============================

In the fine, any AWES changes continuously whether flying  or resting. 

Therefore, an AWES is distinct from its former self.  Some of the changing may lead to a failure of the machine to function; at failure, noticing that the AWES has changed may be starkly easier to identify.  Monitoring changes cannot ever be complete without God-vision; but sensors may trace selected parameters of an AWES while leaving some parameters unmonitored. Skill in selecting parameters to monitor may win profit competitions among competing AWES. And humans unable to be absolutely comprehensive in monitoring capacity, have the challenge of making selections of what to monitor. 
Group: AirborneWindEnergy Message: 27978 From: dave santos Date: 7/28/2019
Subject: Re: Musical AWE
kPower is focused on the 2030 timeframe. Pierre lacks that particular focus, but made time to play piano at an AWEC conference, perhaps thinking that was no lack of focus. Einstein avidly sailed and played violin better than most folks imagine, rather than just focus on non-sailing and non-musical physics. He liked to read the great German philosophers too. It all helped.

Let's hope Pierre's superior sense of focus on kite energy works out even better than what Joe and I do.

Correction: "Music is more closely connected to AWE than almost all other technical fields."






 

daveS: The problem both you and JoeF are having is a lack of focus.  One day it's "Einstein", the next "music" - as though anyone cares about these endless excuses for nothingness.
Sure, anything and everything might somehow be relevant, but you two act as though there is no valid information to actually go on, hoping to somehow "just get lucky" with your aimless meanderings.  You protest my characterization of your approach as "monkey at the typewriter" but continue to divert your attention to every topic under the sun, never developing an AWE system of any kind..  What about "baking cookies"?  Doesn't "baking cookies" have SOME POSSIBLE relation to AWE at some level?  Why not spend a few weeks examining every conceivable aspect of "baking cookies"?  OK now I'm wanting to have a cookie.

You keep saying "power-kites" are "the answer".  You named your effort "k-power" where the "k" stands for "kite", so what we keep asking you is to show us how to use a power kite to generate electricity.  You seem to have endless excuses.  Your two latest are
1) safety so that even 10 kW is dangerous
2) copying my excuse that I am currently too busy with other crap (In my case, including REAL wind energy in a BIG way)
I would say, reason two I can obviously understand but you keep saying you are doing research but you still never come up with anything.  As for reason 1, try starting with kites small enough to be limited in danger potential.  Besides, smaller is cheaper and more achievable.  Get something working that is making any power whatsoever THEN
a) improve the performance and
b) increase the size as you see fit as you progress.
At least get something workable working at some level.
Unless you want to spend the rest of your life just repeating that flying kites or taking a nap "is" AWE.
If that's what you think, why bother even pretending to be involved with actual AWE?


---In AirborneWindEnergy@yahoogroups.com, <santos137@...  

"which other technical conferences decline" is a lie.
Who tells this words lies.
Group: AirborneWindEnergy Message: 27979 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Let Pierre define wind turbine as he wishes: "The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period."

Nevertheless, Wikipedia rightly includes "sails" in its Wind Turbine article-

Wind turbine






 

The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period.
Group: AirborneWindEnergy Message: 27980 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Its sad to correct off-topic false claims, but here's Wikipedia's Windmill Article confirming windmills "take the form of wind turbines" while citing classic sail-based types, and a whole "Sails" section-

"The majority of modern windmills take the form of wind turbines used to generate electricity, or windpumps used to pump water, either for land drainage or to extract groundwater. Windmills first appeared in Persia in the 9th century AD, and were later independently invented in Europe.[5]



[6]
"

https://en.wikipedia.org/wiki/Windmill


Let Pierre define wind turbine as he wishes: "The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period."

Nevertheless, Wikipedia rightly includes "sails" in its Wind Turbine article-

Wind turbine




On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎05‎:‎56‎:‎26‎ ‎PM‎ ‎CDT, pierre-benhaiem@orange.fr [AirborneWindEnergy] <AirborneWindEnergy@yahoogroups.com


 

The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period.
Group: AirborneWindEnergy Message: 27981 From: dave santos Date: 7/28/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Magenn itself put sails on its airborne wind turbine, proving for Pierre that its possible. It was not the sails, but long known Magnus weaknesses that caused the 8 million dollar AWES project to fail. High Cl starting from inherently low lift and power is not a win.

Every rotary WECS is a turbine, including historic windmills with sails, but modern electrical "wind turbines" are not mills that process materials (grind grain, pump water).

Lets here proudly define the "Sail Turbine" class of wind turbines as any rotor with sails. Sailing Golden Age Triangle Routes are the greatest single wind turbines in history, mighty VAWTs ratable at GW scale.



 

Its sad to correct off-topic false claims, but here's Wikipedia's Windmill Article confirming windmills "take the form of wind turbines" while citing classic sail-based types, and a whole "Sails" section-

"The majority of modern windmills take the form of wind turbines used to generate electricity, or windpumps used to pump water, either for land drainage or to extract groundwater. Windmills first appeared in Persia in the 9th century AD, and were later independently invented in Europe.[5]



[6]
"

https://en..wikipedia.org/wiki/Windmill
On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎06‎:‎43‎:‎53‎ ‎PM‎ ‎CDT, dave santos <santos137@yahoo.com


Let Pierre define wind turbine as he wishes: "The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period."

Nevertheless, Wikipedia rightly includes "sails" in its Wind Turbine article-

Wind turbine




On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎05‎:‎56‎:‎26‎ ‎PM‎ ‎CDT, pierre-benhaiem@orange.fr [AirborneWindEnergy] <AirborneWindEnergy@yahoogroups.com


 

The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period.
Group: AirborneWindEnergy Message: 27982 From: joe_f_90032 Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp

Pierre stated for his "we" :
"For an AWE we will never have a wind turbine as efficient as a current ground-based wind turbine, but the space used is far larger. "

That "we" of Pierre's does not include other members and teams in AWE. Rather, the whole question is still very open about AWE; even right now there are some AWES that are more efficient by some measures than current ground-based wind turbines.   AWES need not have rigid massive towers that cost greatly; AWES uses line tethers to reach better wind resources; tethers may be adjusted to let working parts enter best winds. Density of AWES depends on design; AWE is young and dense use of vertical wind frontal space in AWES farms are in visions for development; AWE is not stuck on single small wing with single tether. AWE network with vertical development and broad lateral development may leapfrog past ground-based towered wind turbines in terms of effected use of ground space.

---In AirborneWindEnergy@yahoogroups.com, <pierre-benhaiem@orange.fr
Group: AirborneWindEnergy Message: 27983 From: dave santos Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
The Dutch usage of "Vindmoller" (windmill) has been carried forward to modern turbines, so for these legendary windmill experts, there is no contradiction- a windmill is a wind turbine-

http://xn--drmstrre-64ad.dk/wp-content/wind/miller/windpower%20web/da/pictures/eighties.htm



 

Magenn itself put sails on its airborne wind turbine, proving for Pierre that its possible. It was not the sails, but long known Magnus weaknesses that caused the 8 million dollar AWES project to fail. High Cl starting from inherently low lift and power is not a win.

Every rotary WECS is a turbine, including historic windmills with sails, but modern electrical "wind turbines" are not mills that process materials (grind grain, pump water).

Lets here proudly define the "Sail Turbine" class of wind turbines as any rotor with sails. Sailing Golden Age Triangle Routes are the greatest single wind turbines in history, mighty VAWTs ratable at GW scale.

On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎08‎:‎55‎:‎04‎ ‎PM‎ ‎CDT, dave santos santos137@yahoo.com [AirborneWindEnergy] <AirborneWindEnergy@yahoogroups.com


 

Its sad to correct off-topic false claims, but here's Wikipedia's Windmill Article confirming windmills "take the form of wind turbines" while citing classic sail-based types, and a whole "Sails" section-

"The majority of modern windmills take the form of wind turbines used to generate electricity, or windpumps used to pump water, either for land drainage or to extract groundwater. Windmills first appeared in Persia in the 9th century AD, and were later independently invented in Europe.[5]



[6]
"

https://en..wikipedia.org/wiki/Windmill
On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎06‎:‎43‎:‎53‎ ‎PM‎ ‎CDT, dave santos <santos137@yahoo.com


Let Pierre define wind turbine as he wishes: "The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period."

Nevertheless, Wikipedia rightly includes "sails" in its Wind Turbine article-

Wind turbine




On ‎Sunday‎, ‎July‎ ‎28‎, ‎2019‎ ‎05‎:‎56‎:‎26‎ ‎PM‎ ‎CDT, pierre-benhaiem@orange.fr [AirborneWindEnergy] <AirborneWindEnergy@yahoogroups.com


 

The fact is that there are no sails in any wind turbine. All wind turbines have rigid blades. It is a fact. Period.
Group: AirborneWindEnergy Message: 27984 From: dave santos Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Pierre consistently chooses not to recognize power-to-weight as a key AWES efficiency metric, instead choosing airspace efficiency as more important. kPower argues that highest power-to-weight supports best airspace conservation.

Its true that surface HAWTs do not need controlled airspace at all, but this not a true win. Upper wind is so much more powerful that it can offset lesser aerodynamic efficiency.

Its Ok for Pierre to use "we" in framing his logic, even if he objects when others do; what counts is whether his technical logic is sound.

AWE is more efficient by power-to-weight than conventional wind energy clearly not suited to fly up into better wind.



 


Pierre stated for his "we" :
"For an AWE we will never have a wind turbine as efficient as a current ground-based wind turbine, but the space used is far larger. "

That "we" of Pierre's does not include other members and teams in AWE. Rather, the whole question is still very open about AWE; even right now there are some AWES that are more efficient by some measures than current ground-based wind turbines.   AWES need not have rigid massive towers that cost greatly; AWES uses line tethers to reach better wind resources; tethers may be adjusted to let working parts enter best winds. Density of AWES depends on design; AWE is young and dense use of vertical wind frontal space in AWES farms are in visions for development; AWE is not stuck on single small wing with single tether. AWE network with vertical development and broad lateral development may leapfrog past ground-based towered wind turbines in terms of effected use of ground space.

---In AirborneWindEnergy@yahoogroups.com, <pierre-benhaiem@orange.fr
Group: AirborneWindEnergy Message: 27985 From: gordon_sp Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Dave,

You asked:  “Its the details that are unresolved. How exactly do you launch and land?”

I proposed two automatic systems to launch and land my restrained kite.  The most promising is a lever arm lifting device described in message #23793.  The second is using LTA balloons which will lift the kite to a suitable height and then be retracted. See message #22194.  With both these systems the kite is restrained at all times and the auxiliary tethers are programmed to unwind at a controlled rate based on the main tether unwind rate. (Ratio Control).   
Group: AirborneWindEnergy Message: 27986 From: dave santos Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®
Gordon,

Its easy to propose automatic solutions that may never prove economic or practical. The hard proof-of-concept work begins next, and final commercial validation is a distant milestone. A scale prototype even at 1kW that models full-scale all-modes operations realistically is needed. I am afraid even that will be too much to produce without a large budget and team.

Lets hope someone tests all ST claims and hopes, to settle reasonable doubts. Has anyone ever created a similar lever-based handling system? 

Don't forget landing during galloping, and all such real concerns. Be aware that LTA is operationally very expensive in a cheap-energy scheme. It hardly even pays for major sports events or any other use.





 

Dave,

You asked:  “Its the details that are unresolved. How exactly do you launch and land?”

I proposed two automatic systems to launch and land my restrained kite.  The most promising is a lever arm lifting device described in message #23793.  The second is using LTA balloons which will lift the kite to a suitable height and then be retracted. See message #22194.  With both these systems the kite is restrained at all times and the auxiliary tethers are programmed to unwind at a controlled rate based on the main tether unwind rate. (Ratio Control).   
Group: AirborneWindEnergy Message: 27987 From: gordon_sp Date: 7/29/2019
Subject: Re: Line Gallop and Strum (review and ST shaft context)

Dave,

You said:  “An ST driveshaft is thick and long, so gallop forces are predicted for turbulent gusty conditions”

Consider a drive train with 7 turbines 5 ft in diameter.  The total length of shafts between these turbines is only about 30 ft long.  This length is only about 3% of a 1000 ft tether since the rest of the tether is the cable drive.  At a 45 deg tether angle the lifter kite will be at a height of 707 ft. 
Group: AirborneWindEnergy Message: 27988 From: gordon_sp Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®

Dave,

You said: “Could anyone with a ax walk around and cut your tethers? Then what happens, does a shaft of blades drag for miles?”

I would consider that a 5 tether system is much safer than any of the other AWE systems proposed.  If one of the tethers are severed, then the system can be programmed to automatically retract before the vandal can successfully cut the other four tethers.  Perhaps the blades can be designed so that they slip off the hub if reverse forces of dragging are imposed on them. 
Group: AirborneWindEnergy Message: 27989 From: dave santos Date: 7/29/2019
Subject: Re: Line Gallop and Strum (review and ST shaft context)
A kite cable-drive has its own set of tricky challenges added in. That's not much power from 7 small rotors, if saving the world is needed. a twelve foot rotor would be about the same power.

Oh well, lets see if someone actually builds an ST for that altitude range.



 

Dave,

You said:  “An ST driveshaft is thick and long, so gallop forces are predicted for turbulent gusty conditions”

Consider a drive train with 7 turbines 5 ft in diameter.  The total length of shafts between these turbines is only about 30 ft long.  This length is only about 3% of a 1000 ft tether since the rest of the tether is the cable drive.  At a 45 deg tether angle the lifter kite will be at a height of 707 ft. 
Group: AirborneWindEnergy Message: 27990 From: dave santos Date: 7/29/2019
Subject: Re: [AWES] Re: SUPERTURBINE®
It depends on if there is onsite security, and whether any particular tether is especially critical. The falling hardware would be more hazardous than soft kites falling, and must not drag.

An onsite PilotInCommand and/or VisualObserver (PIC VO) will help, but needs a few MW capacity to meet market rates for kWhr.

Anyway, whoever tries this should be the most careful to identify and resolve all failure modes.



 

Dave,

You said: “Could anyone with a ax walk around and cut your tethers? Then what happens, does a shaft of blades drag for miles?”

I would consider that a 5 tether system is much safer than any of the other AWE systems proposed.  If one of the tethers are severed, then the system can be programmed to automatically retract before the vandal can successfully cut the other four tethers.  Perhaps the blades can be designed so that they slip off the hub if reverse forces of dragging are imposed on them. 
Group: AirborneWindEnergy Message: 27991 From: benhaiemp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Hi PeterS,

I think the most important is to know the ratio of the Power consumption to the Power.

There are few recent experiments: Omnidea (balloon 2.5 m diameter x 16 m span), with a ratio of about 1/4 during reel-out phase, and 1/3 in average. And there is the experiment that is related on the paper, with a cylinder of 3.73 m x 1 m. The results on the figures 4 (lift coefficient) and 13 (power consumption) match the equation 3. So it is a good point.

The power consumption increases by the cube of the tangential speed of the cylinder as it rotates.

The equation 3 (not for a kite) takes the tangential speed cubed, while the equation (for a Magnus balloon-kite) on the chapter 12 in AWEbook2018, page 293, takes wind speed cubed x spin ratio: so the results are quite different. I think the equation 3 is correct. The power consumption is significant. 

I made some extrapolations with a spin ratio of 2, a coefficient of lift of 4 (see figure 4), a wind speed of 13.85 m/s, corresponding to the tangential speed of 27.7 m/s for 530 rpm (see figure 13). And I obtain a ratio that is similar to the ratio of Omnidea's balloon. 


And the paper seems to state that it doesn't depend of Reynolds number. But other papers, of which the chapter 12 (see above) seems to state the reverse, indicating a very high power consumption for a small rotor (0.1 m diameter), becoming lesser as it scales.
There is a lot to learn about Magnus rotors.  

PierreB   
Group: AirborneWindEnergy Message: 27992 From: dave santos Date: 7/29/2019
Subject: kPower's current testing
 A bit of an update on kPower power-arch experiments, where a power kite drives a crosswind cableway (the "arch") in extended figure-of-eight motions. Its taken this long to get simple AWES designs identified from virtually infinite possible rigs. Every developmental prototype is both a step forward and a dead-end in one. Each requires meditation on the complex observations and how to rig next. Both the topologies and geometries evolve; topologies in leaps, and geometries by tunings.

Flying an 8m2 KiteShip OL and 7m2 NASA NPW much like WindSled and others before. The control line rigging art is advancing detail by detail, in safety and handiness. On a fixed anchor in strong wind SS power is scary, compared to kite sports where falling off downwind tames the surges. Finding: It will be necessary to work the depower function closely in strong conditions.

The current architectural direction is to implement a small pilot kite just above the work-cell, to assist launch with a halyard line. Everything else had been flown until worked out fairly well, excepting early-relaunch without walking downwind to reset the kite for launch. Seven pulleys are in the current design, close to what a small sailboat might have. This includes control lines, crosswind cableway PTO, and pilot-lift halyard function.

AWE is now way beyond what anyone knew how to do back in 2007, when this Forum started as a handful of email contacts. AWES rigging could mature rapidly on the theoretic and experimental foundation laid. Its emotionally odd work, where tiny kitemare after kitemare must be experienced and overcome, and everything finally works ~great~. Once all operational modes have been ~perfected~, the kPower game will turn back to decent measured power; then comes major scaling up, if all goes well.
Group: AirborneWindEnergy Message: 27993 From: benhaiemp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
The "we" of Pierre can include who want.
Group: AirborneWindEnergy Message: 27994 From: Peter Sharp Date: 7/29/2019
Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
Attachments :

    Hi PierreB,

    Yes, I agree: the power ratio seems critically important.

    My math is terrible. Could you please tell me how much power is required to spin a cylinder (without end discs) that is 1 meter in diameter and 4 meters long at a spin ratio of 4 and a Cl of 10 in a wind speed of 10 meters per second? And can you estimate the power during the pull stroke if it is used as a long-pull power kite? I’m trying to get an intuitive feel for the concept. The high drag should add to the power.

    For a buoyant kite, the power to weight ratio doesn’t seem to apply. What does?

    PeterS

     

     

    From: AirborneWindEnergy@yahoogroups.com [mailto:AirborneWindEnergy@yahoogroups.com]
    Sent: Monday, July 29, 2019 10:35 AM
    To: AirborneWindEnergy@yahoogroups.com
    Subject: RE: [AWES] The power consumption as the Magnus Effect Balloon or the Sharp rotor scales up

     

     

    Hi PeterS,

     

    I think the most important is to know the ratio of the Power consumption to the Power.

     

    There are few recent experiments: Omnidea (balloon 2.5 m diameter x 16 m span), with a ratio of about 1/4 during reel-out phase, and 1/3 in average. And there is the experiment that is related on the paper, with a cylinder of 3.73 m x 1 m. The results on the figures 4 (lift coefficient) and 13 (power consumption) match the equation 3. So it is a good point.

     

    The power consumption increases by the cube of the tangential speed of the cylinder as it rotates.

     

    The equation 3 (not for a kite) takes the tangential speed cubed, while the equation (for a Magnus balloon-kite) on the chapter 12 in AWEbook2018, page 293, takes wind speed cubed x spin ratio: so the results are quite different. I think the equation 3 is correct. The power consumption is significant. 

     

    I made some extrapolations with a spin ratio of 2, a coefficient of lift of 4 (see figure 4), a wind speed of 13.85 m/s, corresponding to the tangential speed of 27.7 m/s for 530 rpm (see figure 13). And I obtain a ratio that is similar to the ratio of Omnidea's balloon. 

     

     

    And the paper seems to state that it doesn't depend of Reynolds number. But other papers, of which the chapter 12 (see above) seems to state the reverse, indicating a very high power consumption for a smal! l rotor (0.1 m diameter), becoming lesser as it scales.

    There is a lot to learn about Magnus rotors.  

     

    PierreB   
    Group: AirborneWindEnergy Message: 27995 From: benhaiemp Date: 7/30/2019
    Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
    Hi PeterS,

    My maths is not good but I have no choice to try to tee what can be advantages and disadvantages . 

    From the paper:

    Magnus power consumption:

    Cylinder 3.73m x 1 m, area = 3.73 x π = 11.7

    530 rpm  = 27.7 m/s = tangential speed

    Air density = 1.2

    The equation 3 which is on the last page 29, 3.4.. Numerical example from data on the paper:

    0.007 x 1.2 x 27.7 x 27.7 x 27.7/2 x 11.7 = 1044 W (the curve on the figure 13 is on about 1000 W, matching the value by said equation 3).


    Omnidea's ratio of the power consumption/power looks to be similar.


    Another formula (for AWE, chapter 12, page 293, AWEbook2018) gives a different result (lower power consumption to power) by wind speed cubed x spin ratio X not cubed.


    PierreB  
    Group: AirborneWindEnergy Message: 27996 From: benhaiemp Date: 7/30/2019
    Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
    Hi PeterS,

    I chosen wind speed = 13.85 m/s with spin ratio k = 2, that to match 27.7 m/s of tangential speed, but other possibilities for the same tangential speed  would provide a different result.

    PierreB
    Group: AirborneWindEnergy Message: 27997 From: benhaiemp Date: 7/30/2019
    Subject: Re: The power consumption as the Magnus Effect Balloon or the Sharp
    Hi PeterS,

    My previous message applies only for AWE, when I calculate several wind speeds multiplied with different spin ratios to obtain power. So the first message is enough.

    PierreB
    Group: AirborneWindEnergy Message: 27998 From: joe_f_90032 Date: 7/30/2019
    Subject: Gábor Rudas


    Gábor Rudas


    Various experiments