Investigation of the wind climate in connection with double-stall on wings
This project has compiled data to allow the Danish manufacturers of wind turbines and blades to improve their knowledge of double stall. On the basis of the double stall difficulties different types of turbines using different makes of blades have encountered in the Tarifa area in Southern Spain, meteorological parameters and production data from two turbines have been measured for a local site.
It has been known for many years that under certain climates stall-regulated wind turbines will stall at a lower level than expected - this is know as double-stall. In this project the wind climate is investigated in order to find the parameters that cause double-stall. Turbulence parameters are monitored with sonic anemometer as time series, and weather parameters like temperature, pressure and precipitation are stores as 10-minute average values over a period of approximately 1 year. The project will be concluded with a report describing the results obtained including a CD-ROM with results. The report will be distributed to all Danish manufacturers which produce stall-controlled wind turbines. The results may form the basis of better empirical flow models for turbine blades
Part of the acquired data have been analysed to reach an understanding of why double stall occurs. The analysis strongly suggests that a change in power level due to double stall can be a result of several external factors: Rain cleaning the blades. A more or less random change in the wind speed components u, v or w, which in some cases can affect a - probably - fairly thick boundary layer. A change in the high frequency turbulence where the vortex impact is too insignificant to affect an - almost - randomly thick boundary layer. 'Fast' measurements by means of sonic anemometers have been enterd into the database http://www.windata.com. 'Slow' measurements - ie. Climatic parameters - are available in spreadsheet form and will be forwarded upon request to ELSAMPROJEKT
Key figures
Category
Participants
| Partner | Subsidy | Auto financing |
|---|---|---|
| LM Glasfiber A/S |
Contact
Kraftværksvej 53
DK-7000 Fredericia, Denmark
Christensen, Torkild , 79233333, lej@techwise.dk
Øvr. Partnere: LM Glasfiber A/S
