another idea

[yipster]

The designer of the drawings Peter Worsley wrote me back, for witch my thanks. On his site I noted he intends going to show us some calculations and make diagrams. Having proved the concept works i belive ideas like this should be developed further, not strand as other modern sails and wind rotary devices unfortunatly often do. Ideas like this (and a lot of R&D) may indeed revolutionize sailing i belive...

Hi
Your email reminded me to repair the site, I have done so and the link you mention is now working (<http://www.oceanblueone.com/rot.htm>). Several discussion groups have brought up the subject over the last few years, and, it is usual to have believers and unbelievers, believers being usually in the majority. I'm a bit shy of joining in these discussions after one degenerated into insults and I was accused of being a fraud and having "hidden electric motors" etc. I think if those that are interested would read the article I wrote, it explains things well. Also, careful reading will reveal how to make a successful design, although I have never heard of anyone doing this yet - its patented anyway. You are welcome to quote this email in the discussion if you wish.
Peter Worsley

[yipster]

http://www.users.globalnet.co.uk/~fs...deos/index.htm
Where earlier I found the “upwind sailing” anigif and other experimental boats, interesting site!

[Tom Lathrop]

I've been away from the forum for awhile and came back to find this interesting tid bit.

There is no problem with the law of conservation of energy but there is a problem with its interpretation. Mr Worsley's boat can happily go straight into the wind without violating any natural laws that I am aware of. Many others have built such craft that could power directly upwind under windpower alone and I see no reason to doubt Mr Worsely's claim that his will boat will also.

I don't know what he has patented. Probably some parts of the apparatus since the idea and working applications have been in the public domain for a long time.

It's pretty clear that the boat will accelerate into the wind until the force to the drive propeller, derived from the spinning turbine, is ballanced by the drag forces of water and air on the boat That is what the law of conservation of energy says.

I would think that an ice boat would be a better application of the principle since wave making drag would be zero, frictional force very small and the only retarding force would be air resistance. No propeller of course, but a spiked wheel(s) would do nicely.

All members of the flat earth society may ignore this post.

Where is Trouty when you need him?

[dionysis]

I see nothing surprising about the principle. I think the reason it has not become popular is:

1. you can't reef the turbine: a monster in a blow; as solid wingsails are.
2. you would be limited to flat water. Those short chord blades would suffer a lot more from disturbed flow that our forgiving sails.
3. that is a lot of machinery up high.
4. the noise would be incredible.
5. on a reach, while you gain speed with lower wind restance, you lose speed by generating side force.

On the other hand, if you could design a high reving wind turbine, and you got a very efficient water propeller...

This is were the maths comes in. I don't have the calculations at my fingertips, but it is an interesting approach.

We cannot go directly to weather because we need the hydrodynamic side force, which in this contraption is directed sternwards. In all other respects it would behave just like a boat.

[gonzo]

The Law of Conservation of Energy applies to this problem. It tells us that the total energy available in the system is the wind's. Part of it is transformed into torque by the turbine. The rest is drag. For the turbine to produce torque, it needs an "opposite and equal force". In other words, the push against the propeller in the water equals the force of the wind on the turbine. However, because of mechanical inefficiency only part of the wind force gets transformed into torque. Also, there is the extra wind drag and the resistance of the water on the hull. I can't see enough forward force to overcome the drag. As for boats working to windward, they move because there is a residual force forward. It is a small percentage of the total.

[jehardiman]

Originally Posted by gonzo

In other words, the push against the propeller in the water equals the force of the wind on the turbine.

I think I see the misunderstanding that you have. Energy and force are vector quanities. As the turbine spins, the wind generates a force on it which is a vector quanity. We break this force down into two compnents, lift which is perpendicular to the radial axis and drag which is co-linear with the radial axis. Now in this case the radial axis is dead into the wind, therefore only the drag counts against us. Lift because it is perpendicular and tangential has no effect on trying to push the craft back (do the vector math on the torque). Furthermore, lift (for a good turbine design) is about 20 times the drag so only about 5% of the winds energy going into a backward force.

Think of it this way, if your argument was correct, then the steam velocity on a 100,000 shp steam turbines blades would rip the rotor out of the ship. But this does not happen, and rotor thrust is only a couple of hundred pounds.

Yes there is a backwards force, and yes the mechanics lose energy, but the toruqe, and therefore the energy, available is so much larger that the vessel goes ahead. Tell me if you need me to draw you an energy vector analysis and I will.

BTW, this is the reason that turbine designs make poor propeller designs.

[gonzo]

Everyone that believes it is possible uses vectors, force and other measurements without magnitude. The statements make no sense.

[dionysis]

There is nothing for it, you just have to do the maths. Here is an informative first step for wind turbine blade calculations:

http://metp02.mw.tu-dresden.de/Merz_...nergy/Aero.htm

[K4s]

There is a 45 foot trimaran riggeg just like this,vanes that turn a propellor under the boat.(not sure if you still call it sailing).This thing has been cruising around Whangarai harbour and surrounds for about ten years now.Funnily enough it has no problems going directly into the wind or reaching(as in sailing) but doesnt seem to like downwind work
K4s

While none of us brought up in a conventional sailing backround would beleve a boat can go directly up wind. Hundreds of years ago, boats could only go down wind. People are selling short on this upwind stuff again. Simple, flappy sails, probably right. Different (" SAILS ") whatever it may be , held aloft by at least 1 mast, VERY, VERY possible. Face it, nobody is trying. Sailors love the peace-quiet-simplicity of the present sails system. Rich ----I was just watching a sailboat show which spoke of a over 100' boat which has those ROTORS on masts and the boat was throwing a good bow wave. It was on Direct T V in the last 3 weeks. Rich---------Up wind use rotors or propeller types----- Down wind use sail types. Does that sound about right?--- I will split all royalties with the first good design. Rich

[gonzo]

Dyonisis: I checked out that websit. It assumes that the turbine is firmly attached. The calculations don't work for a boat with a propeller.

[yipster]

Fiona Sinclair makes a good read on autogiro boats

[yipster]

although not sailing upwind, not mentioned here yet are the turbosails of Jacques-Yves Cousteau's ALCYONE and Plans for CALIPSO II

anybody has a good story on these turbosails, the savonius and/or darrieus rotor?

[dionysis]

From one of Costeau Society's PDFs:

"A small fan draws air into the 33-foot towers, boosting wind speed over the leeward side and creating forward lift several times the power of traditional sails.

Specifications :

Length: 103 ft.
Draft: 7 ft. 8 in.
Width: 29 ft. Passengers (& crew): 12
Cruising speed: 10.5 knots Turbosails: height 33 ft. 5 in.
Surface area: 226 sq. ft.
Diameter: 4 ft.5 in. "

"The Turbosails work in conjuction with twin diesels and save ~ 30% in fuel."

That is a lot of power generated by the paltry 226 sq. ft. of 'sails'.

An open60 can sail at high speeds across, and downwind. At say 20 knots, the propeller would be doing ...at least it would be turning very fast = some serious gearing = weight.

[trimix]

all the web links seems to be dead ? do you have new ones ?