EcoModder Forum Faster than The Wind - Using only Wind

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 04-02-2010, 09:59 PM #11 (permalink) Master EcoModder     Join Date: Jan 2008 Location: Western Wisconsin Posts: 3,903 honda cb125 - '74 Honda CB 125 S1 90 day: 79.71 mpg (US) green wedge - '81 Commuter Vehicles Inc. Commuti-Car Blue VX - '93 Honda Civic VX Thanks: 867 Thanked 433 Times in 353 Posts so it's creating a back pressure that the wind is pushing... interesting idea.
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 04-02-2010, 10:00 PM #12 (permalink) Master EcoModder   Join Date: Nov 2008 Location: Madison AL Posts: 1,123 The Geo - '93 Geo Metro Team Metro 90 day: 45.16 mpg (US) Thanks: 30 Thanked 40 Times in 37 Posts Learn a little below. Last edited by MadisonMPG; 04-02-2010 at 10:23 PM..
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The physics of sailing

Quote:
 How can boats sail faster than the wind? Lots of boats can---especially the eighteen footer skiffs on Sydney Harbour. Ask a sailor how, and he'll say "These boats are so fast that they make their own wind", which is actually true. Ask a physicist, and she'll say that it's just a question of vectors and relative velocities. Downwind (diagram at left) is easy. If the wind is 10 kt, and the boat makes 6 kt in the same direction, then the crew feels a wind of 4 kt coming over the stern of the boat. The true wind vw equals the speed of the boat vb plus the relative wind vr (see vectors for more explanation). The equation vw = vb + vr tells us the problem: as the boat speed approaches the wind speed, the relative wind drops towards zero and so there is no force on the sail. So you can't go faster than the wind. When the wind is at an angle, we have to add the arrows representing these velocities (vector addition). Upwind (right), exactly the same equation holds: vw = vb + vr. The faster that the boat goes, the greater the relative wind, the more force there is on the sails, so the greater the force dragging the boat forwards. So the boat accelerates until the drag from the water balances the forward component of the force from the sails.

 04-02-2010, 10:19 PM #14 (permalink) EcoModding Apprentice     Join Date: May 2008 Location: N. Saskatchewan, CA Posts: 1,721 Appliance White - '93 Geo Metro 4-Dr. Auto Last 3: 42.35 mpg (US) Stealth RV - '91 Chevy Sprint Base Thanks: 89 Thanked 424 Times in 298 Posts I thought I already had a post on here, wondering what theory this works on. It certainly is not featured on the huge blog, so until I see independent verification, instead of whining about somebody's official gearing rules, I'll assume somebody is using mundane magic on the video.
 04-02-2010, 10:22 PM #15 (permalink) Master EcoModder   Join Date: Nov 2008 Location: Madison AL Posts: 1,123 The Geo - '93 Geo Metro Team Metro 90 day: 45.16 mpg (US) Thanks: 30 Thanked 40 Times in 37 Posts Tack (sailing) - Wikipedia, the free encyclopedia The blades are "tacking" all the time. Another term used is apparent wind.
 04-02-2010, 10:26 PM #16 (permalink) EcoModding Lurker   Join Date: Apr 2010 Location: Oklahoma Posts: 19 Thanks: 0 Thanked 1 Time in 1 Post Ryland: "so it's creating a back pressure that the wind is pushing... interesting idea." I had not that it like that - might a good way to think of it. Bicycle Bob - are you saying you think this is a hoax and what they are claiming is not possible?
 04-10-2010, 02:18 AM #17 (permalink) EcoModding Apprentice   Join Date: Mar 2009 Location: Oregon Posts: 175 Thanks: 0 Thanked 63 Times in 41 Posts Just check out BMW Oracle 2to2.5 X wind speed
 04-11-2010, 10:21 AM #18 (permalink) EcoModding Apprentice     Join Date: May 2008 Location: N. Saskatchewan, CA Posts: 1,721 Appliance White - '93 Geo Metro 4-Dr. Auto Last 3: 42.35 mpg (US) Stealth RV - '91 Chevy Sprint Base Thanks: 89 Thanked 424 Times in 298 Posts I sure wasn't impressed by the blog or any video I've seen, but there seems to be some relevant theory posted at Sailing faster than the wind - Wikipedia, the free encyclopedia The key seems to be to have the wheel acting as a brake, feeding power to the prop to let it pull. It is a mind-bender, all right. Even worse than sailing upwind, or building iron ships.
 05-06-2010, 05:01 PM #19 (permalink) EcoModding Lurker   Join Date: Jul 2009 Location: venice, ca, usa Posts: 9 Thanks: 0 Thanked 1 Time in 1 Post visualization
 The Following User Says Thank You to kerosene For This Useful Post: dcb (05-07-2010)
 05-06-2010, 05:15 PM #20 (permalink) ...beats walking...   Join Date: Jul 2009 Location: . Posts: 6,190 Thanks: 179 Thanked 1,525 Times in 1,126 Posts ...ah, but there's a BIG difference between a "powered" wing and and "powering" wing.