 Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me. |
Forum Index : Windmills : Multiple mill location
| Author | Message | ||||
Rastus Guru  Joined: 29/10/2010 Location: AustraliaPosts: 301 |
Hi to all, Can details be posted to indicate how close 2 dual F&P mills can be located together, and reasons for the specs. Is it possible to use an airfoil like end cap on the blades to control turbulence/minnimise it, and bring them even closer than usual? What are some of the common problems with close proximetry mills. cheers Rastus see Rastus graduate advise generously |
||||
Gizmo Admin Group  Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
Hi Rastus. Well it depends on which way the wind is coming from. As a rule, a downwind turbine should be spaced 5 to 9 times the turbine diameter. So if you have a 2 meter diameter turbine, the closest down wind turbine should be 10 to 18 meters away. For turbines side by side, facing the wind, the figure is 3 to 5 times the turbine diameter ( 6 to 10 meters in our example). The air down wind from a turbine is very tubulent, so you need this extra spacing for the wind to settle. Side by side turbines are different, a turbine creates a bow wave in front of it, and a percentage of the wind will go around the turbine instead of through it ( to do with Benz limit ), so we need to allow enough spacing to let bow wave spoil and the next door turbines bow wave spoil to pass between the turbines. http://www.brighthub.com/environment/renewable-energy/articl es/97151.aspx http://www.elementshealthspace.com/2010/08/04/wind-turbine-s yndrome-part-iii/ http://www.dewi.de/dewi/fileadmin/pdf/publications/Publikati ons/seifert_kroening.pdf Adding winglets will slightly improve the figures, but not enough to be worth while I think. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Rastus The two mills of mine are 14 meters apart and work OK except when the wind is in direct line with both mills, then the second one slows slightly above 10 ms it dosnt seem to make any difference. 
As you can see from the photo the trees to the east of the mill are a more serious issue than the spacing as wind can be very turbulent from that direction. Need a hedge trimmer or a big storm while the ground is soft. All the best Bob Foolin Around |
||||
| Rastus Guru Joined: 29/10/2010 Location: AustraliaPosts: 301 |
Hi Glen, I can picture the wind flow from your description and the spec's and supporting references are informative. The predominant wind directions are N-W-S,NE,SE never from the east, so side by side isn't that easy for me to figure out. However it would be my preference, so the 3 to 5 times swept diameter is favored. Dissappointed about the winglet comment, Oh well? Hi Bob, 14mts is still a little to far apart for what I hoped. Was it a still day when the pic's were taken? I'm asking because the 2 mills seem to be facing different directions. The way the weather is at present you may get your wish with the trees in the east! cheers Rastus see Rastus graduate advise generously |
||||
| VK4AYQ Guru Joined: 02/12/2009 Location: AustraliaPosts: 2539 |
Hi Rastus I live in hope, but in fear of Murphy. No wind that day, not much most times until I get a southeasterly. Bob Foolin Around |
||||
 Print this page |
