[ Date Index ] [ Thread Index ] [ <= Previous by date / thread ] [ Next by date / thread => ]
> So if the wings drive the windward side of the conveyor in a given > direction, what happens with the wings on the leeward side? Do you > have to have some mechanism to have the wing turn around so it > drives the leeward side in the other direction? the blade turns 180 degrees round the end which is just what you need! > There's also the > possible problem that the leeward blades would always be running in > "spoilt" air and causing drag. You may get a throbbing/woosh woosh noise - but the displaced air would be assisting the drive of the following blade - or if it truly is a problem then the blades on one side could be made to feather. > Air at ground level is fairly turbulent > anyhow -- you'd really want to mount such a structure at least ten > metres in the air to get reasonable extraction of energy from the > wind. Same problem with rooftop sites -- and if you could put, say, > a 5m x 1m "belt" on a roof, it's probably going to be about as > effective as a 1.25m radius propeller, but we're talking a much cheaper device here - no precision balancing and you dont have the inherent problems of a windmill - high speed/turbulence at the tips.A windmill can be made 30% more efficient by adding a cowling! I think you could probably make this stuff, in 1m widths for about £1 per meter - so your talking £10 (plus whatever the vertical mounting and generators cost) against a piece of precision engineering. The blades for this device can be profiled so the drive comes mainly from the middle (or wherever) and very little from the edges (for a 'free standing' version) thus minimising any induced turbulence. > which would be far less > problematic to mount, I'd have thought. A windmill on the edge of a house roof suffers enormously from turbulence problems due to the roof. On a simple pitched roof the wind is in more of a laminar flow over the apex - which is where you'd stick this thing - and on an ideal house you can stick one mount either side of the house - easy peasy! To me it looks like its worth a try and I grant there are a lot of things to iron out. I aint no mechanical engineer but I've seen what people did in cotton mills 200 years ago and I bet they could have done it then. Tom te tom te tom > > James -- The Mailing List for the Devon & Cornwall LUG http://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/linux_adm/list-faq.html