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A lot of my interest in sailing is related to my hobby of tinkering. I wanted to bring up an idea I had. When I was a kid about 4 or 5, my parents knew a crazy old man that had a roadside attraction gone to ruin. He had elaborate devices powered by the wind , dolls that road bicycles on carousels and the like.
I was intrigued by the vertical wind mills that powered his machines and had the idea to attach one to a small vehicle like a dune buggy etc.
Later I discovered that long ago someone made a carriage with a gear box on the rear axle coupled to such a rotor. It could drive right into the wind as it was driven by the spinning rotor. I was wondering how that might fair on a boat? Could such a device power a propeller with the wind? If so would it be any real advantage over a conventional device like a sail.
 

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Actually far more interesting, it is possible to design a sail that functions akin to an autogyro, someone did it to a Mirror class dinghy (ofcourse I can't find anything on it on the internet, saw it ages ago on Discovery Channel), allowed it to go much sharper to the wind, with the same speeds as a normal sail.

Ofcourse it does mean your boat has massive spinning blades on it.

In general your idea is considered to be a bit of a loss because resistance of water is quite significant.
 

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Discussion Starter #3
Actually far more interesting, it is possible to design a sail that functions akin to an autogyro, someone did it to a Mirror class dinghy (ofcourse I can't find anything on it on the internet, saw it ages ago on Discovery Channel), allowed it to go much sharper to the wind, with the same speeds as a normal sail.

Ofcourse it does mean your boat has massive spinning blades on it.

In general your idea is considered to be a bit of a loss because resistance of water is quite significant.
Apparently my idea was tried already two people crossed the Atlantic in 1870
in a converted lifeboat. Supposedly it set some kind of record for an "auto gyro" boat with a rotor driving a propeller. In 1933 a guy used a rotor as a sail without a propeller. This might be the one you were thinking of from discovery channel. It was able to go closer to into the wind than a regular sail boat. Apparently the rotor went wild when they let go of it by mistake and tore up another boat.
 

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Not only is it possible to sail into the wind, it is possible to sail downwind faster than the wind:

Skepticblog » Sailing Directly Downwind? Faster Than the Wind

A lot of my interest in sailing is related to my hobby of tinkering. I wanted to bring up an idea I had. When I was a kid about 4 or 5, my parents knew a crazy old man that had a roadside attraction gone to ruin. He had elaborate devices powered by the wind , dolls that road bicycles on carousels and the like.
I was intrigued by the vertical wind mills that powered his machines and had the idea to attach one to a small vehicle like a dune buggy etc.
Later I discovered that long ago someone made a carriage with a gear box on the rear axle coupled to such a rotor. It could drive right into the wind as it was driven by the spinning rotor. I was wondering how that might fair on a boat? Could such a device power a propeller with the wind? If so would it be any real advantage over a conventional device like a sail.
 

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Could such a device power a propeller with the wind?
Sure. Why not?

If so would it be any real advantage over a conventional device like a sail.
Nope. Not even close.

Lots of folks have tried different sorts of ways to power a boat using the wind. No one has yet come up with anything that matches the basic Marconi rig for the combination of cost to build and maintain, ease of use, and efficiency.

But good luck coming up with something. Who knows?
 

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Please explain.
The drag/friction between the boat and the water is FAR greater than wheels turning on wheel bearings on land.

Maybe if the boat was a hydrofoil.. I dunno... I'm just a jazz piano player.

Barry
 

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Barry, what you cite are certainly "problems" but not physical limitations.

The system works on the ground by the differential between the ground and the moving fluid.

There is no reason why a system of a differential between two moving fluids (water and air) wouldn't work. You just need the right size propellers in the air and water.

The drag/friction between the boat and the water is FAR greater than wheels turning on wheel bearings on land.

Maybe if the boat was a hydrofoil.. I dunno... I'm just a jazz piano player.

Barry
 

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Rolling resistance between hard wheels and a salt lakebed + air resistance is a tiny fraction of resistance of a boat hull displacing water. Tiny. Two orders of magnitude different, and the DDWFTTW people had to work hard to make the former setup functional -- barely. Theirs is a special case machine.

I can think of no less sensible way to move a boat thru water than to put a heavy, hideously inefficient vertical-axis wind turbine on a stick, transferring its captured energy (electrical or mechanical) with losses at every step to a propeller, and using that to push a hull. Good Lord. You start with a fairly diffuse energy resource (moving air), then commit serial thermodynamic suicide.;)

Let's take a best-case scenario, simplify the heck out of the model, and come up with some optimistic numbers that may have relevance for people here. A 13' diameter horizontal-axis wind turbine (HAWT) -- which is 4-10x more efficient at capturing wind energy than a VAWT of equal swept area -- can produce just about 2kw (2000W) in ~25kts of apparent wind (which is a LOT of wind). That's about 2.5hp. How fast will an outboard engine that size move your sailboat? How well will it move your sailboat in 25kts of apparent wind? Now: how fast & how well do the sails move your sailboat in those conditions?

Even if we allow the inefficiencies of sails (which are profound) and ignore the dissipative nightmares of turbine-to-prop drives, sails win. A BloKart will still kick the ass of the DDWFTTW testbed: talking VMG, around any test track, in any conditions.

https://www.youtube.com/watch?v=oieUfXyYUBI
 

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Looked nice on a flat sea. Want to take that into a gale with swell and wind waves...a-rockin' and a-pitchin' with that heavy device rotating and vibrating and slamming and banging a-speedin' and a-slowin'?

Anyone have the stability factors for this vessel? (rhetorical)
 

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I wonder if the rotation of the blades would have a gyroscope effect that would actually stabilize the vessel. There are powerboats these days with gyroscope stabilizers rather than those fins sticking down.
 

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I wonder if the rotation of the blades would have a gyroscope effect that would actually stabilize the vessel. There are powerboats these days with gyroscope stabilizers rather than those fins sticking down.
What's a powerboat?
 

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A lot of my interest in sailing is related to my hobby of tinkering. I wanted to bring up an idea I had. When I was a kid about 4 or 5, my parents knew a crazy old man that had a roadside attraction gone to ruin. He had elaborate devices powered by the wind , dolls that road bicycles on carousels and the like.
I was intrigued by the vertical wind mills that powered his machines and had the idea to attach one to a small vehicle like a dune buggy etc.
Later I discovered that long ago someone made a carriage with a gear box on the rear axle coupled to such a rotor. It could drive right into the wind as it was driven by the spinning rotor. I was wondering how that might fair on a boat? Could such a device power a propeller with the wind? If so would it be any real advantage over a conventional device like a sail.
Go to the Junk Rig Association website. There is an article on just that sort of idea in one of their newsletters.
 

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Corsair 24
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id take one of those!
 

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...When I was a kid about 4 or 5, my parents knew a crazy old man that had a roadside attraction gone to ruin. He had elaborate devices powered by the wind , dolls that road bicycles on carousels and the like…
Sounds like about 80% of the Scooby Doo episodes I've seen.
 
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