Sail Directly Upwind (a reminder from the past)

Discussion in 'Hydrodynamics and Aerodynamics' started by Windmaster, Jun 25, 2015.

  1. Windmaster
    Joined: Nov 2006
    Posts: 233
    Likes: 4, Points: 0, Legacy Rep: 56
    Location: Norwich UK

    Windmaster Senior Member

    Hi All

    Not much progress has been made recently on a rig that can allow a boat to sail directly upwind. It seems a useful feature. I make no apology for bringing the subject up again.
    I'm just raising this subject to remind all that such a rig is completely possible. It just needs someone with resources and imagination to build one.
    Here is a short video of my tank testing which demonstrates the principle.
    https://www.youtube.com/watch?v=8Rw_qJytbG8
     
  2. Jamie Kennedy
    Joined: Jun 2015
    Posts: 541
    Likes: 9, Points: 0, Legacy Rep: 117
    Location: Saint John New Brunswick

    Jamie Kennedy Senior Member

    With a similar rig you can also sail directly downwind faster than the wind.
     
  3. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 474, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    There are a few different approaches to sailing directly up wind, but cost and practicality are the usual mitigating factors. When a wind generator can kill it's crew if not careful around one (I knew a guy that was killed with a head strike from a wind generator blade), you can pretty much guarantee, acceptance will be slow at best.
     
  4. Mr Efficiency
    Joined: Oct 2010
    Posts: 8,585
    Likes: 508, Points: 113, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    That really is sailing close to the wind, when you are dodging whirling blades.
     
  5. Jamie Kennedy
    Joined: Jun 2015
    Posts: 541
    Likes: 9, Points: 0, Legacy Rep: 117
    Location: Saint John New Brunswick

    Jamie Kennedy Senior Member

    It's VMG that really matters. It's interesting in theory but not in practice. When sailing with wind turbine driven propellers its really the same vectors as tacking upwind and gybing downwind it's just that the turbines and propellers are doing the tacking and gybing for you, and in both directions at once. Takes all of the fun out of it really, but it's interesting to think about. :)
     
  6. Windmaster
    Joined: Nov 2006
    Posts: 233
    Likes: 4, Points: 0, Legacy Rep: 56
    Location: Norwich UK

    Windmaster Senior Member

    Whirliing blades

    Often, people think "whirling blades" would be dangerous. Well of course you put them higher than anyone would reach or stand! Many people have been killed by aircraft propellers too. Something you have to be careful about (obviously). But just to satisfy those who are worried, I put a shroud of safety ring about the blades on one of my test models, didn't result in much loss of performance. 100_1513.JPG
     
  7. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 474, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Again, cost and practicality are the usual drawbacks. Weight is another issue, particularly compared to a modern composite rig.
     
  8. Windmaster
    Joined: Nov 2006
    Posts: 233
    Likes: 4, Points: 0, Legacy Rep: 56
    Location: Norwich UK

    Windmaster Senior Member

    Its like comparing apples and oranges. A wind turbine driven boat, should not be compared with a conventional sailing craft. A normal sailing yacht is in reality, something of a plaything, and not concerned with getting from one place to another on water, so the inconvenience of tacking is tolerated, even enjoyed (need lots of skill). But if you were looking for a practical wind powered means of water transport - using no fuel. Then the ability to "sail" in any direction would be an advantage. Particularly in narrow channels.
     
    Last edited: Jun 27, 2015
  9. Grey Ghost
    Joined: Aug 2012
    Posts: 194
    Likes: 9, Points: 0, Legacy Rep: 94
    Location: california

    Grey Ghost Senior Member

    It's that "if" that's why you don't see these in numbers.

    Freight and passenger service is driven by schedule. And there is fuel available.

    Most customers are divided into two groups:
    - customers who want to sail
    - customers who use power

    For the recreational segment customers who enjoy sailboats usually enjoy sailing. The rest buy powerboats and you have to demonstrate it's worthwhile to not use power. That's the initial investment, dock space, bridge clearance, draft, trailering, ease of use. For commercial you have to demonstrate you can be competitive with existing service with an advantage strong enough to outweigh the drawbacks. Speed port to port, docking and bridge clearance, deck access, all-weather operation, and so forth.
     
  10. Windmaster
    Joined: Nov 2006
    Posts: 233
    Likes: 4, Points: 0, Legacy Rep: 56
    Location: Norwich UK

    Windmaster Senior Member

    Point 1. Why do people enjoy sailing? Does the difficulty make it more rewarding? As someone has already said, making it easy, "takes all the fun out of it".

    Point 2. Perhaps it is a mistake to think of just power - or just wind. Why not use the wind power technology in addition to motor power and as a fuel-saver when conditions allow. I believe they are working on this in San Francisco with the wind assisted ferry. Although this is a wing sail and not a wind-turbine. A wind turbine could easily be incorporated in the design.
     
  11. Jamie Kennedy
    Joined: Jun 2015
    Posts: 541
    Likes: 9, Points: 0, Legacy Rep: 117
    Location: Saint John New Brunswick

    Jamie Kennedy Senior Member

    It would be interesting for a sailing barge. I love those things. Stayed on one the first night I was in Holland in 1977. Beautiful. But if I had a live-on-board barge or narrow-boat as some call them, I would want to be off-grid, with a combination of wind-solar power. If the prevailing wind was often enough up canal and down canal I would have a wind turbine to charge batteries. When there was extra power available after the batteries were topped up I would even use it for cooking, heat, and hot water. If I wanted to go up stream or downstream I would have an electric motor running off the batteries, but with a wind turbine providing power as well so on a good day the wind power could go directly to the electric motor without charging and discharging losses. I think I would try to design and have machined a custom made variable pitch propeller, driven by large diameter permanent magnet motor that could also be used as a generator. The same design might also be used as the wind generator. It would be fun to play around with such a beast. I am not sure I would call it sailing, but it would be fun to mess around with. I am not sure I would want the wind turbine to be much larger in diameter than the barge itself, and it would have to be lowered for bridges. A single blade design would be interesting. Of course I would have to be able to make a living also. There's always that. I think such a beast might be more fun in theory than in practice. Perhaps a micro-barge might be an interesting beginning for someone, but once you go small you can probably take and gybe your way up and down narrow canals anyway, but it would still be fun to play around with the other stuff, and much cheaper if down-sized.
     
  12. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 474, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I'd be willing to bet, that a well designed sailboat can out perform the "wind powered" prop thingie, to any windward target and certainly if some serious sailors (foils, multi hulls, ocean racers, etc.) where employed. I think the size of the prop you'd need to be remotely competitive with anything other than a Ingrid type of yacht, would be just too large to be practical, reasonably light weight and safe to be around, ducted or not. I'm basing this across several parameters, but frictional loses alone from the gear system necessary to make this a viable consideration, should kill any hopes other than these theoretical musings.
     
  13. Windmaster
    Joined: Nov 2006
    Posts: 233
    Likes: 4, Points: 0, Legacy Rep: 56
    Location: Norwich UK

    Windmaster Senior Member

    To reply to what Jamie said about the diameter of the wind turbine being smaller or larger than the beam of the boat. I did quite a few experiments to find out how small I could make the diameter of the rotor and it still having the ability to go direct to windward. Here are some pictures of some models I made http://www.sailwings.net/gallery/001.html I found that at least for a catamaran, the rotor could be smaller than the beam of the boat. Some I made were very much smaller and they still worked. It does of course depend upon the windage or drag of the boat versus the thrust of the propeller.
    In reply to PAR, we are not really talking about being competitive with sailboats. It's the apples and oranges thing again - not the same ballpark. I don't know why he has put "wind powered" in quotation marks. It really is wind powered. There is no doubt about it.
     
  14. Manfred.pech
    Joined: Apr 2010
    Posts: 595
    Likes: 79, Points: 28, Legacy Rep: 319
    Location: EU

    Manfred.pech Senior Member

    Peter, thank you for coming up again with your great work. Boatdesign has had already some very interesting threads about this concept of turbine powered boats (for instance http://www.boatdesign.net/forums/pr...ats-how-many-out-there-they-viable-14182.html and http://www.boatdesign.net/forums/sailboats/directly-against-wind-33963.html and http://www.boatdesign.net/forums/boat-design/sailing-directly-windward-27000.html ). As time goes on there seem to be more and more interest not to waste oil and ruin the climate. But the solution of wind turbine powered boats which really earns interest did not find enough attention.
    As I found out the idea is not new. The first sketch I saw is of 1714 and since those days there might have been hundreds of models, tests and research, but none has found its way into mass production - not even to recreational vessels, though there have been some (curious) boats.
    [​IMG]
    [​IMG] (BOOTSHANDEL 2/2000)
    [​IMG] (PAHLSTEK 3/2000)

    There have been some developments which did a good job as you can see within the collection of Fiona Sinclair (Autogiroboats): http://fionamsinclair.co.uk/yachts/auto/index.htm
    Well known is the work of Jim Wilkinson ( of Aviation Enterprises, GB) with his 26ft Prout Sirocco Catamaran with a rotor of 7,62m diameter (Yacht 7/1987, Multihull International 9/2000) and Jim Bates (NZ) with his 9,75m long Cat TIKI II ( Yacht 2/81). In Germany the idea of a "Mühlenschiff" found a group of shipbuilding engineers of the technical University of Utersum and they developed a well working vessel (Yacht 7/87) which was successfully tested. The further development was killed by german bureaucracy.
    But there will be new attempts when oil will be more expencive. May be something like this: https://www.youtube.com/watch?v=IzGCYaJbf0A
     

  15. tom28571
    Joined: Dec 2001
    Posts: 2,473
    Likes: 115, Points: 63, Legacy Rep: 1728
    Location: Oriental, NC

    tom28571 Senior Member

    Paul, I'd say that current discussions and demonstrations are about on par (pun) with the Wright Flyer in December, 1903. It has been over 60 years since Bernard Smith demonstrated that a sailboat could exceed true wind speed in VMG to windward. If a fan boat can go through similar drag reduction advances such as used on the last America's Cup, might its VMG not exceed a tacking sailboat to windward? That means foils, of course, which would not be required to resist leeway and thus not have the drag associated with that.

    My knowledge of the physics limitations of the two systems is to weak too know for certain, but I don't think that the answer is at all clear. I am certain that the answer is in the drag/thrust ratio though.
     
Loading...
Similar Threads
  1. Philip
    Replies:
    22
    Views:
    672
  2. Mikko Brummer
    Replies:
    52
    Views:
    2,415
  3. Grunf
    Replies:
    12
    Views:
    1,096
  4. wesley Sherman
    Replies:
    10
    Views:
    681
  5. Federico Ferretti
    Replies:
    3
    Views:
    1,077
  6. schakel
    Replies:
    4
    Views:
    1,084
  7. Yull
    Replies:
    10
    Views:
    1,334
  8. Manfred.pech
    Replies:
    7
    Views:
    1,579
  9. andysailor
    Replies:
    4
    Views:
    1,165
  10. CocoonCruisers
    Replies:
    75
    Views:
    7,227
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.