Flettner and Magnus Force Powered Boat

The Flettner magnus rotor uses the same principle as a pitcher uses to throw a curve ball. A spinning sphere or cylinder moving through an airstream creates a force perpendicular to the airstream just as an airplane wing does or a sail boat sail. This acting in conjunction with a keel would allow the boat to tack upwind just as a conventional sailboat does. Like a conventional sailboat, it could not go directly upwind but would have to tack from side to side.

https://en.wikipedia.org/wiki/Rotor_ship

http://physicsbuzz.physicscentral.com/2015/05/the-physics-of-sailing-how-does.html

Ok great! Thanks Rixter.

since the winddirection may vary, wouldn't it be more usefull to place the rotor in the water beneath the ship then in the air since it's just creating a flow.

On the boat they use an engine to turn the huge flettner rotors.

I just don't get why someone would do that, wouldn't the propeller convert the energy more efficient?

It's the wind that propels the boat. The rotor just redirects the wind force, the same as a sail does. It does not create the flow. Its advantage over a sail is that you can tack closer to the direction of the wind.

If you put it in the water it would create drag, and if it were turning create a force at right angles to the motion of the boat through the water, which would be of no use in propelling the boat.

Here is an experiment that you can do. Get a beach ball and toss it to someone, but as you toss it, spin it so that the top moves toward you (backspin). The ball will be deflected in the upward direction. Here is the same trick done with a basketball dropped from a dam.

http://www.independent.co.uk/news/science/watch-this-basketball-fly-thanks-to-the-magnus-effect-10395549.html

Thank you didn't know that. Actually became smarter today, yeah! :p

And yeah watched that ball dropped into the dam, looks great!

If there was a strong movement of water at right angles to the ship's course, you could be right, otherwise not.

Remember, you still do need "wind" to "sail" with this system......Watch the video I just posted, all will be explained I feel.....

It is not a propulsion system all on its own.

The rotors are turned by electric motors, generating thrust from the prevailing wind, using the curved ball principles used by soccer, tennis, cricket and baseball players for many years.

Jacques Cousteau's boat "Alcyone" used that principle.

A good way to gauge how well some new technology works, is how quickly it gets adopted....this cover is from 1925

True that.

But look at the stuff from Nikola Tesla, his inventions show up in the car.

His Wardenclyfe tower still exceeds our technology

The Wardenclyfe tower thingy didn't really work though....in fact it was based on a theory from Mahlon Loomis and the misunderstanding of the nature of radio waves....at the same time Marconi was actually succeeding in wireless transmission based on sound scientific principal... Working in isolation on ground breaking technology rarely succeeds in anything but madness...

I'm glad Tornado remembered that also. I remember reading about Jacques-Yves Cousteau's Alcyone in his magazine. "The Cousteau Society, Calypso Log". At one time I was a member of the cousteau Society and got the "logs" on a regular basis.

It seems like it would be much simpler than tending the sails 24/7.

I saw her in Seattle one time, but was not able to get on board. I had been a low-level contributor to the Cousteau Society for a time. My father-in-law (one of the designers of Seattle's Space Needle) had been a significant supporter and had met one or both of the Cousteaus, but apparently they were off the boat and out in town that morning, so no way to hook up. That would have been really interesting, though, especially to a former seafarer such as me. (This was around 1987.)

I guess then it uses its propeller, as it does have one......

You should watch this video, although its in German, the animations are well done:-

http://www.youtube.com/watch?v=2pQga7jxAyc

Remember, that ships have for 1000s of years, have not been able to sail directly into the wind (with some relatively modern exceptions), so they "tack, to "make" the direction they want. Its relatively well understood in the sailing world.

I see nothing preventing this ship "tacking" as well.......

Also, planning of voyages will probably take into account the prevailing winds at the time of year when the voyage taken. Attempting to sail through the "Doldrums" will of course reduce the efficiency generally speaking, but still may be the most "efficient" direction to take at certain times of the year....

There are so many variables, that I can only post in a general manner.....but I am sure that the people crewing that ship will know exactly what needs to be done.....

Never compete with this.....

http://www.dailymail.co.uk/sciencetech/article-2314635/Hydroptere-The-worlds-fastest-sailboat-hoping-sail-Pacific-record-time.html

My, oh my! This is the first decent posting in memory that requires knowledge and thought.

My understanding is that it takes less power to rotate the flettner rotors then it would take to propel the ship via a propeller - at the same speed. Wind energy is partially used to propel the ship thus reducing its fuel consumption.

Why not use a vertical axis savonius wind mill (very similar to the flettner rotor) to generate electric power, . . and then to use this power to drive the propulsion system?

This type of system can be used to propel the boat regardless of the direction of the wind, . . . something that sailboats or the magnus effect boats can not accomplish. One has full control of the boat propulsion with such a system.

Just how much wattage do you think the windmill will generate? ...and how much wattage do you think will be needed to drive the propeller?

..."Our motor is a 7-kW unit, equivalent to 10 hp...."

http://www.oceannavigator.com/September-2011-1/Are-electric-motors-ready-to-replace-diesels/

I always was concerned with noise and the boat tipping too much with that weight up there. Un-stayed, it could fatigue and break off at the bearing.