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Ribbon-arch-rotating kites
and its cousins where "ribbon" is taken to extremes into snakes, Darrieus complexes, Selsam cylindricals, Faust-ribbed playsails, etc.  [Herein is mostly considered flip-winging with secondary overtures of Magnus-effect processes in  complexes with their attending low-end lift/drag challenges.]  (news invited*)    RRK, RRKs

The top edge of ribbon moves downwind. 
Top to back... when looking downwind.

Generally these kites are ribbon-like with the entire ribbon or its sections rotating with axis traverse to the wind while being held with two kitelines; i.e. flip-winging. Think of extended Magnus-effect kite with more flexible wing.   SkyBow, Ribbon kite, rotating playsail, rotating-ribbon arch kite, rotating-ribbon kite,    These are autorotation kites using the Magnus-effect. Magnus effect rotating kites that have the rotation axis bluntly normal to the stream.    Think of a rainbow in the sky that is autorotating as the rainbow interacts with the wind.  Double-ended terrain-held VAWT might be considered the superset that holds flexible rotating-ribbon auto-rotating kites as a subset.  "anti-gravity rope" (but they are not round ropes).  Jim Mallos and Tony Frame have worked in RRKs.     Magnus-Robins effect.   Spin rates?  Section spin rates?  Ribbon design for arch sections?   Anchors.  Groundgen RRK system?   Micro-skygen RRK?  Texture? Shape? Curves? Skybow rotary kite. Ribbon rotary kite.  Rotor arch.   Rotating arch kite system.   Skybow Rotary-Wind Engine.   Skybow rotary arch kite.   Autorotating ribbon kite.

Mr. Big. Photos.

Challenges: design, sizing, limits, sectioning, uses, scientific description,  trappable torque,  tensions, rotation speeds, limits, wind speeds, width, precise specifications, safety, tensions, launching alternatives, landing alternatives, farms,  free-falling moorings, spar-separated free-falling moorings, tugged by two parallel flying aircraft,  etc.    Invite furthering by all.   Flying ribbons.   Sectional swivels?  Swivels at mooring.  Interference in a farm of such kites?  What are the stall and re-start behaviors of particular designs?  Success stories?  Bringing in nanotech materials? Laminate materials (say Kevlar and foam, say foam and carbon-tube foundation, etc.).


One dealer claims:
"It creates more lift per pack volume, area, and weight than any other aerodynamic device known to man."    Discussion on such claim is welcome for this folder herein.

  • Recall that the Magnus effect will generally stink for power-out compared to the structure needed. The lift is weak and return-side drag is toxic. (Figure ways to guide flow to power side while shading return side ingeniously and some gain might be had).   Add in flygen penalty for the flygen choices (there are many Magnus-effect groundgen AWECS schemes), no sweep or crosswinding, etc., and it is hard to see how a very low L/D (~1/1) ribbon arch can ever compete with the many higher L/D (3-15/1) that we have in hand. Do not be fooled by claims of (static) pull, as mere tension without displacement does not generate power; though tension may double-serve to keep low-mass taut to support some torque transfer. Look for niche uses of the generally lower-performing Magnus-effect schemes.  Fencing and sky meshes of Magnus-effect schemes may find their special-uses. On the plus side, the ribbon is a cool flying-rope (albeit a flattish kind of rope)  idea and could generate micropower at swivel junctions.  Selsam-Darrieus Magnus-effect rigidized cylindricals may find niche success.   Sky complexes of interacting Magnus-effect elements might have some surprises yet; discussion is open (e.g., consider the difference of side-by-side-same-rotation handedness compared to side-by-side alternating rotation handedness, and then with possible flown shadowing of the return interfaces.)  Recall that costs to hold a system lifted and anchored are real.  Bring your device to a fly-off to see how it competes with other systems.
     
  • v?

How much energy may be obtained from rotating-ribbon kites?  How scalable is this technology?  World records for kite-energy from this category of kites?  Double-ended terrain-held VAWT might be considered the superset that holds flexible rotating-ribbon auto-rotating kites as a subset.  Is there an AWECS niche here? The low L/D might even be helpful for mining torque for driving generators.   See related article here.

Niche application of rotating ribbon kites?  Advertising.  Decoration.  Celebration.  Kite-energy production. Play. Recreation.  Bird scaring might be explored with this type of kite.  Sound maker. Education.

Section the long bow where sections rotate at their own speeds and with their own end swivels might be explored to limits of scale and function.

Consider central pilot lifter kytoon or kite for a vast array of rotating ribbons with groundgens at each of the many mooring points, each mining a bit of the torque. What are the limits to such consideration?

Consider using two separate kites with one tugging left and the other tugging right; stretch a rotating ribbon kite RRK between the kitelines of the two kites. How far could this arrangement be taken? 

Consider also incremental stiffening of the ribbon to the point the ribbon becomes a stiff rotating wing held between the two L-R kites or kytoons.  Or held by terrain; then we approach http://tech.groups.yahoo.com/group/AirborneWindEnergy/message/663 matters, which see; such get into Darrieus matters, terrain-held Superturbine snakes, etc.

Non-rotating ribbons, playsails? Such are close to non-rotating sled arches, paragliders, etc. We put these in contrast with rotating ribbons that positively rotate (more than zero rotate).  Example: http://www.ipass.net/lewsther/kites/ribbon.jpg    Example also: free-falling kite that is a manned paraglider using Jalbert parafoil as wing.      The non-rotating wings have a potential of better L/D  over the rotating ribbon kites.

Contrast systems that are not RRK flexible ribbons, but are still two-mooring arches of rotating elements:
  • Notice the contrast of an arch train that is NOT a rotating ribbon kite: 2kiters
  • Another example of a non-rotating arch two-moored system here.
     
  • But consider cousins which are not RRKs but are still arch trains with segments that are rotating  flip-wings (having a secondary aerodynamicMagnus-effect) VAWT. For example, one unit might be like:
  • JpF       
     Sample of one unit element: HERE.
     
  • Notice that the side-by-side collection of VAWT is also quite distinct from pilot-kite-lifted arches that assemble a collection of HAWTs.
     
  • Here is a non-flying natural arch that was formed in part by wind erosion.
  • Non-rotating playsail kite of two moorings: File:Cervolix2.jpg    News and notes are invited.
  • AWES5943   Kite Arches for Crosswind Power
     

 

Consider replacing the ribbon with a torque tube while setting the two anchors with one downwind some; mount multiple autorotating HAWTs on the torque tubes. Have LTA severe lifting kytoons at left and right for lifting the complex. Have several rungs of the static ladder while the element rungs are fully dynamically rotating. Generators could be at the left and/or right ends of each rung.  Is this a call to Selsam and his SuperTurbine  with sky serpent rungs of a tall multi-rung ladder to the skies.  Multiply the shown system  to  kitefarm.

http://www.movinglikewater.com/Images/super_turbine.jpg

Kite Lines article by Steve McKerrow and Valerie Govig
The high-arching Skybow Is it a rotor kite? An arch ribbon? Neither? Both?

Kite Lines, Winter 1997-98, starts on page 52 and continues.

I have study copies form the source of Jim Mallos photobucket site.
Posted some links in AWES forum on April 27, 2013.
Study file in Kites/ at EKS.
 
Bullroarer      AirborneWindEnergy/message/9099
SKYBOW

Image warm up for a SkyBow musing:

Roy Mueller shares a SkyBow musing:

"What is the bar set at....

What is it's highest level?

Could this be a pole vault apparatus... ?    MONEY- sports?
Maybe something yellow?  Bananas- bananas?
Maybe like a.... jump rope.. that was soft to the touch
and that would come in a pair?.


An invisible jumping... Jump Rope...
because it is a mystery how fast it can spin... or even that it is spinning at all...
and it come in a pair... like a seed... in all sizes.

Maybe a Chromosome?. CHROMOSOME ZONE PARK - crown-zone park... KING FIELD... A SkyBow park.  What would that look like?

Maybe Saturn.... with a McDonald's.... with two half-circle rings visible..

Hummmm.... I wonder sometimes and cry when no body else can see it. Like every day. But now :0

Maybe others could see it too.

Isn't spin-off technology great?

Tesla---Skybow."


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