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Wind-Powered "Greenbird" Seeks Land-Speed Record

Posted by timothy on from the beautiful-pictures-too dept.

Mike writes with this tantalizing excerpt: "Dale Vince of Ecotricity and engineer Richard Jenkins are setting up on the salt flats at Lake LeFroy in Western Australia, hoping to catch the right breeze and break the wind-powered landspeed record of 116.7 mph in their sleek wind-powered vehicle, the Greenbird."

38 comments

  1. Transportation? by Anonymous Coward · · Score: -1, Troll

    What does this engineering-masturbation have to do with transportation? It's not like it's useful for anything other than some weird bragging rights.

    1. Re:Transportation? by Anonymous Coward · · Score: 2, Informative

      You may not know, since your hobby seems to be bitching about the accomplishments of others, but when you try new things, you tend to learn new things.

      Things that can be put into practice in other ways.

    2. Re:Transportation? by gyrogeerloose · · Score: 2, Insightful

      What does this engineering-masturbation have to do with transportation? It's not like it's useful for anything other than some weird bragging rights.

      From TFA:

      The team plans to take the knowledge they gain from these experiences and apply it to the real world, incorporating aspects from the design into the next generation of vehicles and micro turbines.

      So there may be something useful achieved. But even if not, it's still a pretty cool thing. Besides, not everything has to be useful.

      I think you need to get out more.

      --
      This ain't rocket surgery.
    3. Re:Transportation? by Chris+Burke · · Score: 1

      I think you need to get out more.

      He can't afford to, if he's going to continue being constantly useful!

      --

      The enemies of Democracy are
    4. Re:Transportation? by SQLGuru · · Score: 2, Insightful

      A lot of knowledge is gained by these types of endeavors. Even if they seem pointless.

      Why do motor companies continue to invest in various forms of automotive racing? It isn't like they can sell F1 cars to very many people? They do it because they can learn things under extreme conditions. They learn about tire wear, aerodynamics, engine performance, etc. (and of course, they also get brand exposure, but that is a side benefit).

      Setting the wind powered land speed record will aid in aerodynamics, harnessing wind (which could be useful in converting it to electricity) and I'm sure several other areas. And in the process, they get to put their names in the news (and possibly the book of world records).

      And besides, have you ever written a program "because you can" or maybe modded a case "because you can" or built a robot "because you can"?

      Layne

    5. Re:Transportation? by not-my-real-name · · Score: 1

      What does this engineering-masturbation have to do with transportation? It's not like it's useful for anything other than some weird bragging rights.

      Well, since engineers can't get girlfriends, what other outlet do they have?

      --
      un-ALTERED reproduction and dissimination of this IMPORTANT information is ENCOURAGED
  2. Faster than the wind? by MrMunkey · · Score: 0

    Can someone explain how they could travel 3 to 5 times faster than the wind is blowing? I'm thoroughly confused on how that's possible. Is the vertical wing producing less air pressure towards the front providing forward momentum?

    1. Re:Faster than the wind? by haeger · · Score: 3, Informative

      I hate to do this but...
      http://justfuckinggoogleit.com/search.pl?query=sailing%20faster%20than%20wind%20speed

      >;-)

      .haeger

      --
      You are not entitled to your opinion. You are entitled to your informed opinion. -- Harlan Ellison
    2. Re:Faster than the wind? by Anonymous Coward · · Score: 0

      what they don't tell you is the driver eats a ton of chili hours before and uses the resulting ass-force to give a boost. Ass-force is measured in multiples of wind-speed.

    3. Re:Faster than the wind? by RingDev · · Score: 0

      The vertical hard sail is actually a wing, just like an airplane wing, there is a high pressure side and low pressure side when air flows around it. I would imagine the most challenging part of the drive is jump form going slower than the wind, where the sail is presumably acting like a sail, to going faster than the wind, where the sail acts as a wing.

      Bah, who am I kidding, they're just going to pull it behind a truck until they get it up to above wind speed. They're only looking for the big number at the peek, not how they got there.

      -Rick

      --
      "Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
    4. Re:Faster than the wind? by dezert_fox · · Score: 1

      They're traveling across the wind, not just being pushed straight forward by it. Think of a racing sailboat keeling over to the side--clearly it's not being pushed from behind (or at least, not always).

    5. Re:Faster than the wind? by etnoy · · Score: 2, Informative

      Being a sailor, I get that queston quite often. The explanation is simple and appears to be a bit contradictory; the sails generate lift from the wind created by the boat's own movement. If you are familiar with vector addition, it is trivial to see that the resulting "apparent wind" is the "true" wind (the wind speed and direction as seen by a stationary observer) added to the the speed of the boat, both which are vectors with different angles.

      This is also the reason why iceboats (and probably also the "boat" mentioned in the article) almost exclusively sail with the wind from the side, not higher. They are faster than the true wind speed, and the direction of the apparent wind turns against the boat.

      The phenomena of the apparent wind has a lots of uses in the world of sailing, and I'm just scraping the surface here.

      --
      Quantum hacker.
    6. Re:Faster than the wind? by famebait · · Score: 1

      the sail is presumably acting like a sail, to going faster than the wind, where the sail acts as a wing.

      Soft sails act as wings too, unless you're on a run. So really it is acting as a sail all the time. And a wing.

      --
      sudo ergo sum
    7. Re:Faster than the wind? by Anonymous Coward · · Score: 0

      OT, but I had to say I love your sig. Except maybe it should read, "Be socialists." :)

  3. 3-5 times actual wind speed? by fishybell · · Score: -1, Redundant

    TFA says that they are able to attain speeds 3-5 times the wind speed at the ground. I know with tacking you can move against the wind, but how do you go faster than the wind? As always, the article is low on technical details, anyone know how this is possible?

    --
    ><));>
    1. Re:3-5 times actual wind speed? by BitterOldGUy · · Score: 4, Funny

      Well, if you've ever seen the Coyote and Road Runner Cartoons, you'll know that the crew on the boat blows really hard into the sail, thereby creating a much larger velocity associated with the relative wind, increasing the "lift" of the sails and thereby propelling the craft faster than the wind. Now, if you place a large amount of ACME TNT behind the craft, the crew, out of shear terror, will blow even harder and thereby adding a few more knots to said velocity of the craft.

    2. Re:3-5 times actual wind speed? by eln · · Score: 4, Funny

      They use a rocket engine. The fuel was derived from oil, which used to be dinosaurs. The dinosaurs used the wind (or "air") to breath, and the plants (and other dinosaurs) they used for fuel also used the wind in a similar fashion. Thus, the vehicle is technically powered by wind.

      See? This green stuff is easy if you just put a little thought into it.

    3. Re:3-5 times actual wind speed? by Red+Flayer · · Score: 2, Informative

      Yes, I know how this is possible, and if you took elementary physics, you should be able to figure it out.

      I'll give you a line of thought to follow, to get you started.

      What happens when the wind hits the sail? Force is exerted on the sail, which is transferred into forward momentum of the vehicle. What happens when the wind hits the sail from directly behind the vehicle (in relation to its path)? What is the force exerted by the wind on the sail when the speed of the vehicle is equal to the speed of the wind?

      OK, now what happens when the wind is coming from an angle (say, 45 degrees)? And what happens when the speed of the vehicle is equal to the speed of the wind? What force is exerted on the sail then?

      --
      "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
    4. Re:3-5 times actual wind speed? by Anonymous Coward · · Score: 0

      In sailing you have something called apparent wind. This is the direction and speed the wind appears to be coming from as the vessel moves. As the vessel moves faster and closer to the direction of the wind (modern sailboats can travel close to 30 degrees off the direction of the wind) the apparent wind increases in speed and moves more towards the front of the vessel.

      The thing that they are really having to fight with here is drag and downforce. The faster they go the more the wind is trying to flip the boat sideways.

    5. Re:3-5 times actual wind speed? by gyrogeerloose · · Score: 1

      I took a course on sailing once. The instructor was fond of pointing out that a sailboat is actually sucked forward rather than blown forward. Repeatedly. I think this guy may have had issues beyond a fuzzy understanding of the physics involved but he wasn't totally off the mark either.

      --
      This ain't rocket surgery.
    6. Re:3-5 times actual wind speed? by DRAGONWEEZEL · · Score: 1

      you use a more than 1 sail to catch the deflected wind. I just googled it and came across this page.

      http://www.physclips.unsw.edu.au/jw/sailing.html

      --
      How much is your data worth? Back it up now.
    7. Re:3-5 times actual wind speed? by Tenebrousedge · · Score: 3, Informative

      For more information, people can go to the Greenbird web page or to the relevant wikipedia page.

      --
      Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
    8. Re:3-5 times actual wind speed? by randyest · · Score: 2, Insightful

      No, you just sail. One may sail faster than the wind in a craft with only one sail.

      --
      everything in moderation
    9. Re:3-5 times actual wind speed? by Anonymous Coward · · Score: 0

      They didn't teach physics at my elementary school. :(

    10. Re:3-5 times actual wind speed? by sumdumass · · Score: 1

      The wind pushing you forward creates another wind because you are moving through the air. Imagine coasting down a hill on a bicycle or skateboard. If the wind directly behind you is pushing you at the same speed, they will cancel each other out. So you hit the wind at an angle so the wind created by you moving through the air isn't clashing and canceling each other out. Now, they trim the sails into a wing of sorts that instead of being pushed, it is actually being pulled by lift. As long as you are moving in a direction the lift increases by the surface area of the wing and the angle to the wind.

      This is also how a sail boat can sail into the wind. Although there, it is very inefficient and they don't get a lot of speed. But the answer is that the sail becomes a wing that creates lift along it's axis which is vertical and ends up getting pulled by the lift more then pushed by the wind.

      This is also a main difference between a fan and a propeller on an aircraft. The propeller is shaped like a wing so the lift gives you more forward movement (power) then the friction of air crossing the blades and being pushed behind it. If you were to fit a fan with a propeller and make it turn at the same speeds, it would pull the fan over.

    11. Re:3-5 times actual wind speed? by BungaDunga · · Score: 1

      I had a physics teacher who was fond of screaming "THERE IS NO SUCH THING AS SUCK!" repeatedly.

  4. Tinker Toy Fun! by Underfoot · · Score: 0

    It looks like something I built with tinker-toys once. I hope theirs holds together better than mine did.

    --
    I mentioned tinker-toys once in a post - now I'm modded down for life.
  5. apparent wind by Anonymous Coward · · Score: 2, Insightful

    http://en.wikipedia.org/wiki/Apparent_wind

  6. Try tacking on the 405 by Anonymous Coward · · Score: 0

    not good

    1. Re:Try tacking on the 405 by gyrogeerloose · · Score: 1

      I've seen drivers doing it but alcohol was usually involved.

      --
      This ain't rocket surgery.
    2. Re:Try tacking on the 405 by ozphx · · Score: 1

      This thread delivers the lol.

      --
      3laws: No freebies, no backsies, GTFO.
  7. How does it go? by dontPanik · · Score: 1, Funny

    It doesn't have a sail. How does it go?
    Someone tell me how stupid I am.

    --
    "Computers are useless. They can only give you answers." - Pablo Picasso
    1. Re:How does it go? by gyrogeerloose · · Score: 3, Informative

      Really stupid ;-)

      Just kidding, of course. The thing does have a sail, but it might not be obvious to the uninitiated. It's that thing that looks like a vertical airplane wing. As you may be aware, the sail on a modern sailboat functions much like the wing of an airplane. The rigid sail on this landsailer is actually much more efficient than a cloth sail.

      --
      This ain't rocket surgery.
    2. Re:How does it go? by Eternauta3k · · Score: 1

      Yeah, I thought someone had stuck a R/C glider onto the roof

      --
      Yeah. Would you choose a neurosurgeon who pokes around people's brains in his spare time? I wouldn't.
    3. Re:How does it go? by Thelasko · · Score: 1

      The rigid sail on this landsailer is actually much more efficient than a cloth sail.

      This has been tried on boats too. From Wikipedia:

      Two Stars and Stripes cats were built, one with a conventional soft sail (Stars and Stripes S1), and the second with a hard sail (Stars and Stripes H3) built by Scaled. The hard sail proved faster and was used in defense.

      After the 32nd America's Cup, the hard sail yacht was bought by Mexican yachtsman Victor Tapia and sails in Mexico. The soft sail yacht was bought by Steve Fossett and used to set speed records in various yacht races.

      Yes, "Scaled" refers to Scaled Composites of Space Ship One fame. I've had a very difficult time finding more information about this yacht. I wonder why that design hasn't become more popular. I suspect it was made illegal for racing.

      --
      One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
    4. Re:How does it go? by etnoy · · Score: 3, Informative

      I wonder why that design hasn't become more popular. I suspect it was made illegal for racing.

      Rigid sails are extremely inflexible compared to their soft counterparts. Every wind needs its own sail shape; different wind speeds, directions, wave heights, etc. all require different shapes. There is no rule against rigid sails, it's just too hard to bring dozens of huge metal foils on a boat.

      --
      Quantum hacker.
    5. Re:How does it go? by kesuki · · Score: 1

      "There is no rule against rigid sails, it's just too hard to bring dozens of huge metal foils on a boat."

      besides which converting a modern ship from diesel to sail powered is very hard, that's why they're using kites, which can easily be added to a conventional freighter, to reduce the fuel consumption. http://www.treehugger.com/files/2008/03/beluga-skysails-cargo-ship-kites.php

      --
      https://www.gnu.org/philosophy/free-sw.html
  8. Thanks! by DRAGONWEEZEL · · Score: 1

    I realize now that I mis-interpreted my original reading of that page. Thanks for having me go back and check it over!

    --
    How much is your data worth? Back it up now.