With state-of-the-art materials, how close to ever-up LTA AWES could occur?

Aerogel insulation? 

Moisture mining slowly as needed aloft for keeping air-inflated kytoon inflated with humid air?

Solar energy heating during shine?

During night, how much energy draw would it take to use wind energy partial

to keep the humid air heated?

Little-to-no He nor H2 nor methane ...

Maybe a matrix of interior chambers that slow heat loss. 

			Aerogel - Wikipedia, the free encyclopedia Aerogel is a synthetic porous ultralight material derived from a gel, in which the liquid component of the gel has been replaced with a gas. The result is a soli...
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Exterior skin as well as interior curtains?

DaveS,

"At least we know of no AWE patent seriously blocking us..."

So KiteGen does not have blocking patents...So your reproaches against MassimoI were unfounded...hum,hum... 

PierreB

Wecs on top of a wecs is a fine model for arch lift kite automatically generating.
Remember...  a wee ram air cell kite  tied above the back of a lifting sled makes the pair gallop together
Cyclically pumping the tether.

Not to be confused with a Mothra trying to flap

Galloping pumping kite pair must be another one of those cc4.0 NC BY SA types

Just as an overloaded small ram air kite vibrates and judders (jellyfishing?)  a massive kite in a similar regime may also judder and shake it's tethers.
That can be  used
CC4.0 NC BY SA

"...robs power more-or-less at the 10W-per-kilo ..." In % please DaveS?

Sky WindPower uses autogyro (tilted rotor harnessing wind energy)-helico (torque transmitted in the generator which works also as motor during take-off) mode while SkyMill uses autogyro (thrust) mode.

I do not know references about wind energy efficiency. DaveS wrote: "The major power loss comes from tilting the rotor disc, with a reduced frontal harvesting area, and a less than optimal output trade between advancing and retreating blades." The reduced frontal harvesting area is also the price for lift. The "less than optimal..." is a subject for study. The joined paper shows a rotor alone has a far better ratio as within the whole machine. But wind energy production is another problem.

My idea to gather tilted rotors integrated within kite is for giving a possibility of scaling-up without too big elements and without problems from a farm with a forest of long tethers. I am supposing both SWP and SkyMill have positive answers for energy production but I do not know more about them.

PierreB

*Here is an old post from GrantC.

"Hi Theo and Pierre,

Autogyros or Gyrogliders, wind turbines and helicopters are all related but are quite different.  With a wind turbine the blade angle of attack (AOA) tends to be negative (below 0 degrees). This negative angle directs the lifting force of the airfoil more into torque. With a helicopter the AOA is positive (above 6 or 8 degrees) Most of the force is directed to lift but of course needs to be powered around with a motor. An Gyroglider is the exact middle with a AOA from 2 to around 6 degrees.  The middle third of the rotor acts like a wind turbine and add torque and rotation to the system. The outer 1/3 of the disc act like a helicopter and adds lift.  The torque and the lift magically balance each other. The variable is the rotors RPM which goes up and down with the wind speed or the amount of wind collected.  (the rotor discs AOA or how much it is tipped into the wind)

The problem as I see it, is a airfoils lift goes up or down as a function of the square of the wind speed. (actually cubed in theory).(this is true up to the point of the airfoils drag rise as it gets close to Mach 1, but that is another issue unique to rotors).  With concepts like Skywind power or Doug S. Super Turbine (TM) they are taking torque out of the autogyro rotor. Doing that they are slowing the rotor down and loosing lift by the square.  This is like stealing the goose the laid the golden egg and adds an complex control balancing act.  How much lift can you steal by tapping the torque of an gyroglider rotor before you fall out of the sky?. (the answer is not very much, if you ask a aurogyro pilot who has touched the rotor break in flight, not a recommended maneuver. Freeflight and tethered flight are quite different so it is not a perfect example.) One could say reeling out by 1/3 windspeed does the same thing with the ground gen, cross wind maneuvering helps bring some of the lift back.  (However, there is a big limiter to cross wind power and that is tether drag, which also goes up by the square (cube?) as the speed increases.  Having 2 to 4 tethers really adds killer drag. To fly fast, say 200mph like Makani or Ampex you need a short single tether under 1000 meters or the tether drag will be overwhelming. (I don't buy that they are only flying low because of the FAA)  At jet steam altitudes gentle shunting crosswind maneuvers can help with gyrogliders up to a point where they begin be a detriment due to the drag caused by the long fast moving tether.

Letting the rotor free spin and find its natural RPM there is no concern about over speeding the generators so that control problem is not an issue. Also changing from wind turbine to helicopter and back as Joby, Skywindpower and Makani are proposing can be done but is very complicated with helicopter style swash plates, motor/generators and such.  If they are to work for months at a time without maintenance this mechanical complexity is an issue. The pure Gyroglider uses a bearing and some simple hinges in the hub making in mechanically robust concept working in almost pure tension.

"Concepts like the rotokite, Jobys latest auto rotation style patent, and other twin kites will work well at low line angles, low in the sky. From 0 to 45 degrees. Basically they are just working like a big tethered downwind wind turbines.  The same could be said for Makanis circle looping kites.  To go above 45 degrees they kind of need that middle third of a rotor adding torque into the system so it can drive the outer third back into the wind.  Also the hub (not just a tether connection between kites) is an  important component.  There is desymmetry of lift in a rotor.  The hub helps transfer torque generated on one side to the other keeping the system in balance. This I have learned this is critical especially at the start up.

If you are satisfied with working 500 to 1000 meters with tether angles low to the ground (under 45 degrees) most of these concepts will work fine.   To go higher to the jetstream levels you need to get your single tether above 45 degrees or your line length gets crazy long and adds too much drag. We have found the gyroglider rotor with a ground gen is one way you can do that.

The biggest question in the end is ROI.  If your ROI is 2x what a HAWT is, is there enough profit for the risk the investor takes or would the prudent investor just invest in twice as many HAWT and accept a lower more stable return.  With the SkyMill Gyroglider we are seeing a preliminary 4x improvement in ROI over HAWT in select locations. We find this very encouraging."

DaveS,


Poor.All the economical and industrial world comprising serious (with working prototypes) AWE players work with patents. By telling " Both of you seek investors based on your patents, without convincing prototypes." ,you make a bad unfounded accusation based on personal attacks as usual, proving one time more your lack of ethics.

PierreB

Thank you Doug. Indeed "you are not an idiot" is a big compliment. "This is the first sensible post..." Do you hint at the last one with an attachment : ""...robs power more-or-less at the 10W-per-kilo ..." In % please DaveS?..."?  
 

PierreB

DaveS,

Again please see and try to understand my previous posts about http://wheelwind.com on rim driven problems and the possible transformation by the last proposed schemes as possible cellules. Current tests about integrated rotors (http://flygenkite.com ) are also tests about updated ASWES (http://wheelwind.com ).

PierreB

Norbert L. Osborn

Wind Energy Device

circa 1995

Patent US5484257 - Wind energy device

			Patent US5484257 - Wind energy device A device for generating rotating shaft power from atmospheric air includes an airfoil. A partition is disposed within the airfoil along the length thereof. The part...
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Flygen with PTO interior of the wing ...

~ JoeF

In the news note there is reference to some further NASA activity. 

Will They Fly? Wind-Power Alternatives 

Buffeted by Technical Squalls - NBC News

EnerKite - Technik und Team - KurzTrailer

video. 2:09

Yeah the NASA news was short on tech reveal but promising

Rails and rail tracks have played in aviation from early years. Study of each rail use might be interesting for AWE developers. 

Without prejudice to earlier rail uses in aviation 

is this first mention in AWE community circa 1988 

by robust thinker Gaudencio A. Labrador of 

Patent US5435259 - Rein-deer kite and its control systems

			Patent US5435259 - Rein-deer kite and its control sy... What has been created is a new device that is used to take benefits from the energy of the high altitude winds for purposes of doing work and to produce...
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"said ballast weight 35 may-also take the form of a cart on wheels rolling on land or on a rail track or a sled sliding on ice."

Tags: moving anchor, traveling anchor, rail, track, rail tract, rail track, 

Note: Centuries old is a tech of generators driven by railed wheels.

I must correct me on a previous post,quoting from it: "Patent US5056447 - Rein-deer kite ,Figure 10 being the only relevant document JoeF...provides".

https://patentimages.storage.googleapis.com/US6327994B1/US06327994-20011211-D00029.png    is another link from JoeF's last post on the subject, showing Fig.27 from Gaudencio A.Labrador's more recent patent.

"Fig.27---illustrates a wideface multilevel balloon-kite that has downward sidewalls, carrying wind turbines to convert the high altitude winds;    " , being a variant of balloon-kite from sus mentioned patent of which some quotation as "

2. Description of the Prior Art

The existing balloons today that are being used as an

air-born transportation are the spherical and /or the

elliptical forms that just drift along the flow of the wind

and cannot be maneuvered to cruise transverse to the

wind, they being not in the form of a wide-faced kite,

and none of those balloons have ever been tied to a

moving anchor on the ground to change the path of the

drifting balloon." shows the purpose as building a trains of balloon with flat sides like a kite. Note that I do not know any flat balloon, since the internal pression produces curved shape.

But a train of balloon-kites is very different as a flat surface (no balloon, no train) I propose, and the purpose as sail boat is different from general wind energy production, that explaining this. If no by the same a plane (having turbine) would be the same as an helicopter (having turbine).

So all documents presented by JoeF show some level of prior art but not really relevant prior art.To find relevant prior art we must find the reasons of cited devices. For what I propose, the reasons are: scaling-up without too big elements, and without a forest of tethers. Beginnings are: autogyro-like are good but taken alone, the tether is too long, and lift is too low under jet-stream, so by linking several rotors within simple surface, scaling-up is possible, lift is improved (both by small lighter rotors and by surface)  and forest of tethers is avoided. None of cited documents (patents and Kpower's _ numerous and useless since without analysis _ videos) describes such purposes and the structure for them.Note also I learn more from DougS's "negative posts" than from Kpower-KiteLab-DaveS's "positive posts":in one side some rigorous reflexion about wind energy, and some main direction (tilted rotor) to resolve problems like land use, take-off, regularity...; in the other side, multitude of "possibilities" of non-analysed schemes. The "negative posts " can be a way to reduce the duration of R&D for first step. The "positive posts", with hundreds videos, with hundreds improvements of improvements of...bad schemes, can be a way for 1000 year more in R&D.

PierreB,

http://flygenkite.com