More laddermill / spidermill ideas

From what I have seen, yes. By this feature it becomes a sort of Laddermill.

For a ribbon I would think of vents like for parachutes, but I don’t know if it is possible and how.

Bit of a long link? But it does provide valuable information about dimples?
This might please windy who think I’m making him the homework mule?
I was giving @Windy_Skies an opportunity to join in? I might as well left a sign up saying gone fishing? Is it really much that dumb a idea? That windy quakes in his boot? I don’t know? Is he embarrassed? Yes I’ve more to read up on. Happy to take it at my own pace.
Other things to consider?
https://www.google.co.uk/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwis3r6Q8Jr9AhUYilwKHecsBdQQFnoECAwQAQ&url=https%3A%2F%2Fwww.newscientist.com%2Farticle%2Fdn1746-hexagonal-dimples-boost-golf-balls-flight%2F&usg=AOvVaw1JvSn-TVJsYate2JfYRD_o

I know it possible to make a hex tile sheet? They do regularly make them on 3D printer? You also have vortex shedding
I previously broach this with

So location are key?
@Windy_Skies previously mentioned wind speed over tall buildings?
The chances are the number of components can be dramatically reduced? To a direct drive and belt? As the main components? We all might remember?

Essentially if you go down the cassette head coil route? It could be incredibly easy to do? Not only could it be cheap time will only require 5mins to set up in the field? Might require longer if attach to a building? With plug and play in mind? Easy peasy lemon squeezy!
Totally off the shelf parts too.
@PierreB yes it like ladder mill in certain respects? But unlike ladder mill? this won’t need the extra kite sails. It should only need the tape and rollers and best?

The tech is out there! it just about pulling it together, get some numbers? Then cross reference that with competitors? Chances are you would undercut the the current energy sector? Big fish, little fish problems?

Effect of dimples on a golf ball and a car

LINK:

Effect of dimples on golf balls and cars: A Review
Olabanji Y. Shonibare December 26, 2014

Abstract
The purpose of this review is to determine the effect of dimples on the drag force on a golf ball and a car. Dimpling a golf ball and a car has reverse effects on the drag. Presence of dimples on a smooth ball causes a reduction of the total drag on a golf ball. Although no study on the effect of dimples on the drag on vehicles was found, inference were drawn from studies conducted on an airfoil (streamlined body). We discuss how an increase in surface roughness of a streamlined body leads to an increase in drag. Since most recently built cars are stream-lined, it was concluded that introducing dimples on a car would lead to an increase in drag.

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A similar device but working with a box including two motorized wheels turning in the opposite direction, with the string between the wheels:

ZipString - Can you push a string?

You may have heard the saying: “You can’t push a string” It generally means that something is impossible, insurmountable, or hopeless. Because, who could push a string, RIGHT? Well, now when someone tells you, “You can’t push a string.” Pull out your ZipString, and do the impossible anyway.

Additional explains in French language on:

@dougselsam @PierreB @Rodread @AweEnthusiast
Yes essentially Pierre that one way to do it? With the wind acting as the drive unit? As I’ve previously discussed with magnetic gears. it might be possible with this example to reduce friction? which will help with over all efficiency? I don’t thing there much modifications need to the control circuits? There would be room for dump loads? It something that size I was thinking could charge a mobile phone/ table?

The best thing is it can be an of the shelf assembly?

A bit clearer:

A driven roller is clamped to a driving roller, or both can be driving, some distance from that is a second such unit. Between them is a drum that holds your rope drive. Between the drum and both of the roller units there is an installation where you attach and detach the kite tethers to the loop. To start, after you’ve wrapped the loop in the way that it should, you add kite tethers to the loop as the loop unwinds. The kites need to be flying crosswind to have it make any sense for energy production, but don’t need to for first testing of this ground station. The drum has a protrusion in the middle. To wrap the loop around the drum again, you let the loop catch on this protrusion and rotate the drum. Power is generated by the two, or four, or more, to reduce needed clamping force and with that tether wear, driving pulleys.

The two pulleys in a unit are clamped together by some spring mechanism, which both needs to be strong enough to clamp on the tether strongly enough, but also allow the pod that connects the kite tether to the loop through.

As the kites need to fly crosswind at high speed, I think they should fly in circles around the loop, which seems to necessitate a robust pod design.

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Just in case anyone didn’t comprehend the meaning of my post, please let me clarify. The two passages below, encapsulate the theme of the abstract:
Dimples do NOT reduce drag on streamlined bodies.
The only reason they reduce drag on a golf ball is they reduce the area of vacuum behind the golf ball. That is because, being round in shape, a ball is not very streamlined, and so has a lot of drag (vacuum) on the back side. The dimples serve to delay separation of the boundary layer from the surface, thereby reducing the area of vacuum behind the ball. Otherwise, for most reasonably-streamlined shapes, such as a car. dimples add roughness, which adds drag.

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So there’s the difference that
A string shooter accelerates the loop at the bend - low near ground - using driven wheels (or high speed blast of air as in the intro video to this … dangerously nearly a topic
While Ladder mill accelerates the rope (downwind upward) using wind drag effect on lifting elements (kites) attached to the loop, while the loop drives wheels at the bottom junction. (never tested)

It’s been imagined in laddermill that on the rising side , soft parafoil kites are full and held by tethers lower down the line like normal kites, until the weight and drag of collapsed return side kites pulls the topmost kite over and thus leading it’s topside into wind and collapsing onto the line loop heading downward.

At the bottom they head into a sympathetic driven system (I like this pipe elbow joint smooth guide shape here - OK… but still needs a gear or bullwheel or something) which protects and resets the kites while it retards the rising kites line

go build it

Here’s the Original Version from 1977:

Auto-Oriented Wind Harnessing Buoyant Areal Tramway:



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Quickly scribble this down this morning.
Just to give a visual?
With some idea where it could go?
Version 3. the belt could act like a streamer? Adding stability? Operation can be at altitude? Use coflow jest as a feature?
Honestly the list is endless?
@PierreB @Rodread @Windy_Skies @dougselsam @AweEnthusiast.

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There are multiple glaring issues with that, the manual launch and landing, the giant wheel in the sky, the gigantic lifter kite needed, and it being drag based, but the main idea of the two kite attachments points is not a bad start I think. I think the ascending side will have a higher tension so that should be on top, but then perhaps you’d get (more) interference with the wheels.

One variation to make it crosswind is to instead use a single loop and let the kite swivel around the loop tether.

I do kind of like the streamer idea. For now you can replace the lifter kite (or lifter kite train) with a tower, and get a 0 degree elevation angle, no kite control needed, laddermill. The con is that you need either airgen or a two stage rope drive.

You can combine it with Doug’s idea of attaching kites to the loop in such a way that they catch the wind in one direction and don’t in the other. And there is also my idea of then also letting the kites circle around the loop tether.

I think you need a funnel that looks like a C from the top around the pulleys to prevent the kites getting stuck in the pulleys. And better to have more pulleys clamping on each other to reduce pressure needed.

You only need a tower, some pulleys, a loop of string, and some kites, so I think this is something anyone should be able to experiment with.

The streamer as it is now is rubbish. The things I would have liked you to find for yourself earlier is that you need to increase the frontal area to catch more wind, and that drag based anything is a bad idea, for example, but you need to experience that for yourself or see videos of it in action to really understand that.


Here is an idea:

A plywood base, on that say 6 pulleys in a semicircle. Each original pulley, or a fraction of them, has another pulley pressed against it, and a generator attached to it. Make a box around this with a channel cut out (rounded hemi-dodecagon) that goes above the path of the loop. Where the loop enters the box there is a C-shaped funnel (or something like a combination of that with the tip of a syringe needle with a slit along the shortest length of it) that directs the kite tether arm to the channel. This syringe needle tip / C-shaped funnel combo and the pod and the kite tether arm work together to orient the kite tether correctly and prevent the kite getting stuck in the box. The pod can have an arm attached to it so that the kite tether doesn’t need to go into the box, and to decrease the possibility of the kite tether getting wrapped around the rope drive.

But what if the kite wants to go along the opposite side from the kite tether arm along the box. To accommodate that I think the box needs to not be rectangular, but have this same rounded hemi-dodecagonal shape cut out from one side so the kite tether can more easily be dragged along this, even if the length of it is low.

You can work on this before thinking about towers and kites.

A crosswind version of Laddermill was studied. I remember that its name was “Spidermill” but it does not look to be an official name. Laddermill - #8 by PierreB.

The pdf is available on Comparison of concepts for high-altitude wind energy generation with ground based generator | TU Delft Repositories. I reproduced the Figure 4:

Figure 4 Ockels Landorp

@Windy_Skies it might seam a little strange to some people? but modify a hand towel dispensers?

As you mentioned box shaped units?
Should be easy to make it as long and you like?
Also


What you described sounds much like a paper mill set up? If it loops around multiple rollers? Inside the box unit? This could them have complementary gears? To gear up and gear down what the wind can probably provide? This version would be on the heavy side?
Total doable? Wheel barrow wheels? Spindles? Even plywood preforms?

@PierreB I can see the point your making. Self opening pocket attached to the belt would be good? As it reminds me of


But for wind applications? There are similarities to laddermill? The self opening bucket would help out a lot. There will be need for spool flanges but that easy to to? Heck I could to turn them out of wood on a pole lathe? I’d even sat thinking I could stick a few bath towels together? For the trial run before adding motors? To reinforce the towel you can’t stitch paracord banding? Much like the steel mech in car tyres? Might annoy the wives if the lovely new towel go missing?

The major issue that could be encountered is when the weather goes full tempest? Rain stops play? How dose rain slow it’s performance? Might be able to get round that with a hydrophobic coating? That something that will need to be bridged when it comes to it?
@Rodread @dougselsam any ideas?

As for a returning c section that can be as simple as 1*4 boards? If available?

[quote=“Windy_Skies, post:751, topic:1610”]

This was an attempt, by me as a mere teenager, with no existing wind industry, which I was already telling everyone was in our future, due to touring the Niagara Falls Hydroelectric plant and being told it powered a good portion of New York State, including our house 70 miles away, and having sailed boats, so I knew the power was there, and with a background in making and flying a lot of kites as a kid.

I knew someday the world would stumble with confusion into an AWE frenzy, with a lot of attempts at it, and wanted to at least document that whenever some wannabe genius thought of by then, I could prove I had already thought of it decades ahead of them as a mere lad. This single early drawing was not designed to be a “final answer”, so much as showing a simple example of a configuration that could actually work, with nobody else even thinking about AWE at that time. I just did not want the future people to think they were the first to think up such a simple device.

Apparently you don’t really understand what you are looking at.
The upward-traveling side exposes each sail to full wind resistance, pushing downwind, away from the wheel. Then as the sails climb, their angle of attack changes until they are sailing upward using some lift. As they round the top, the sails are in full lift mode, which serves to elevate the sails and cables on the downward trip, while presenting very little downwind force, so the downwind lines remain taut as the sails are pulled downward. Since the sails are flying downward like a glider at that point, they are prevented from contacting the upward-traveling side. This same dynamic applies to the version cleverly called “laddermill”, which I had predicted would emerge decades later. A million simple variants are possible. So far nobody has ever even tried to build a single one.

Please don’t mistake every detail in this one-off hand-drawing by a teenager as encompassing every variant I had in mind. It was just an example, so I would have something to show the world, so at some future time, they would realize I had been light-years ahead of anything they could think of, decades later.

By 1980, I had read my first book on wind turbine design, ordered from the U.S. Government Printing Office. From that I got a quick education. It was not a very thick book, but it contained all known designs and their advantages, disadvantages, and operating characteristics.

One of the most important was lift versus drag, and that any device with working surfaces that traveled downwind, then upwind, tended toward being a “drag device”, whereas a device with working surfaces traveling 100% crosswind, and holding their ground against downwind travel, tended more toward being a “lift-based” device, which offered much higher speed and efficiency, therefore, while I still saw the advantages of my original “aerial tramway”, I thought “SuperTurbine™” represented a probable improvement on the concept.

From there I had pretty much decided that this new, yet similar device, that could “hold its ground” against downwind travel, using 100% crosswind travel was the answer, rather than traveling downwind, then upwind, which was more drag-oriented, so my mind turned toward various versions of SuperTurbine™ - simply taking the best existing wind turbine design, and stretching it out at an angle to the windflow to expose each rotor to its own fresh wind flow.




One major advantage of the SuperTurbine™ concept for AWE, was the angle of the driveshaft necessary to expose each rotor to fresh airflow, neatly matched a typical angle of a kite tether. So it seemed like a fortunate favorable match of operating characteristics, with the upward angle of the “driveshaft-tether” served three purposes simultaneously:

  1. Elevating the apparatus in the manner of a kite tether, at a similar angle;
  2. Placing each rotor at an angle that helped to elevate itself and the entire structure;
  3. Allowing fresh wind to reach each rotor.
    By 1981, I was a Physics Major at University of California at Irvine, and with the world’s first windfarms suddenly appearing in nearby Tehachapi, we were learning how wind turbine rotors worked, and how to derive the Betz coefficient on-paper, from a strictly theoretical standpoint.

In response, I was showing my further drawings of SuperTurbine™ to my Fluid Mechanics Professor, and was kind of surprised that he did not quite seem to appreciate the significance of my way to multiply the power of a wind turbine to an almost unlimited extent by stretching it out into a third dimension.

This I saw as fortunate, realizing it would be unlikely that anyone else could even understand what I was thinking, so I was probably at the forefront of a new paradigm in wind energy, from several angles. I realized I was on my own and would have the opportunity to develop the idea myself, which I subsequently did.

So I’m glad I had the sense to document my initial ideas way back in the 1970’s, so decades later, I would be able to show that I was at the forefront of early thinking about improved wind turbines and AWE. It would be nice if I were given a little more credit for my ORIGINAL thinking, which preceded most other early awakenings to the possibilities of multi-rotor wind turbines especially, but also to AWE in general.

I was one of the founders of the movement, and along with the Makani effort, my early protoytypes helped place AWE “on the map”, ushering in today’s annual AWE World Conferences, which happened at least partially in response to my having already won a Popular Science Invention of the Year in May, 2008, a year before the first World AWE Conference.


LINKS:

So of the three AWE “players” at that time, me, Makani, and Joby, I was the only one who brought a working demo to the conference, and it flew unattended, even overnight, for three (3) days, operating without requiring any computers or human attention, charging a bank of batteries inside the support vehicle.

This first AWE Conference was fun, but it was also apparent that most of the people attending were pretty much clueless about wind energy. There were a few people who knew a lot about flying kites, but I could tell they were incapable of comprehending wind energy, which remains true to this day. I could see most of their ideas and proposed approaches were scatterbrained, untargeted, and incomplete. I surmised that it would be quite some time before, having tried everything else, people would begin to realize that some version of SuperTurbine™ offered some of the best possibilities of success.

Now that so many other ideas have failed, it’s encouraging to see things slowly shifting over toward SuperTurbine™, exploring some of the myriad possibilities the concept offers. I look at it as “The SuperTurbine Army”. Someday, as the other ideas fall by the wayside, it may be recognized that I was one of the founders of airborne wind energy, or maybe, if none of the other approaches work out at all, The Father of Airborne Wind Energy.

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You’re right, I didn’t. Thanks for the correction and the comment. You’ve done and made some nice things, which is difficult, and which have also influenced my thinking.

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So something like this perhaps, where the shape of the funnel is probably wrong, as now the arm for the kite tether will just run into it instead of being guided by it. The pulleys, inside, are not pictured. The extra protrusion is to prevent the kite slipping behind the object and getting stuck.

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Yes, it rather khopesh shaped. which lead me into making another suggestion. The outside edge can be blade shaped? If you were to take that route?

I can see that It make some sense to do things this way.
image
With the belts/tethers safely enclosed there’s less risk of injury to the operator. Due to it being a belt guarded system. I had thought if anyone was to take the multiple pulley approach to thing? You could have simple contact wheels


Cheap and readily available?
You can have something that just runs past the top edge or goes in an s pattern along the arc? Weaving in and out? Depends on scale? Will depend on size and radius of the outermost edge. As torque is needed ? the further the edge is from the Centre the more torque can be applied. The pulling can have a simple self centring crown to it? Or be as simple a by cycle wheel? If taking the khopesh route? Then not only has it found a name? It’s found easy of construction and scaling abilities. You could imagine a few of these stuck in the ground? As tall as current wind inferstructure? Just depends how many idle wheels will be needed?

I imagine something like a band saw set up?

Both modifiable? both very easy to replicate?
I’d imagine the tethers coming out the tip? Then return near the protruding part/ handle?

I was going it be simple and just have a half pipe shape inside a box? Current down on build time and assembly? But I do like the idea of it looking knife shape! Also leave it open to vortex modifiers and vortex drivers? Especially near the tip and exit points? Would make for some funky futurist architecture? All it can be self aligning much like the weather vanes of old? Even could have it looking like a rooster? The chickens come home to roost?

Might be one way of upgrading the existing infer structure? With a enlarged swept area?

There are place which we could take a leaf out of?
image
As the engineering is already there to take advantage of?
I like the design potential! Real fancy string shooter!


I was sat thinking about belt types? This is more commonly know as crochet? I’m demonstrating the small length so you get some idea of texture materials? There another technique encountered as a Viking. take ages and conventionally done by hand as I know no machine that can do it?

Nalbinding. Is very old and maybe the reason knitwear became used to things like crochet or kitting. Because it’s quicker and fastest? I can hand braid even know how to make scoobies.

which can be machine braided? In quantity? Though don’t know who would do them?

You can get Viking knit chain bracelets? Though it rare to see large quantities or huge length? Due to how time consuming it is? I’ve made steel core knit chain in the past?

Don’t know if it would be useful here?

Just a few more loop ideas?

Version 2. Here I assume the kites hang below the loop and only allow them to go down the same side of the ground station as the channel. I also put an angle between the two red pieces, the channel and the protrusion, so that there is only a problem if the kite approaches in between the legs of the V-shape that they make with each other. I didn’t draw the funnel, or other solution for the point where the kite tether attachment enters the channel. Notice the protrusion extends in front of the channel so that the kite tether is guided toward the channel.

This concept, with the multiple smaller pulleys, I think is better than what you normally see where a big wheel is used, as you can make the distance between the two sides of the loop arbitrarily large, like you see with ski-lifts, and the wheel isn’t in the way. And small pulleys are simpler and cheaper than giant wheels. You would still like to use as big a pulley as you can get away with to try to reduce the number of them and with that their friction loss. Bigger pulleys should also be able to handle the possible kite tether pod better and need less clamping pressure.



Sort of what I’d imagine it to look like? Obviously main components not displayed just the c channel.
The oval shape help guild the loop around. There can be concealed pulleys in the top and bottom. But also in the mast structure itself? Like blades of grass swaying in the wind? Blades of the wind? Can be as tall a skyscraper or pocket side? About to affix to a vehicle of outdoor structures? Personally I wasn’t going to make it too complicated?
If anyone else wishes to chime in feel free?
@PierreB @dougselsam @Rodread @AweEnthusiast
It has also occurred to me that the streamer idea?
Looks awfully a lot like?

So potential for and advertising board? With something like rolling type?