This project is part of the wind energy meteorology efforts of the institute which is closely related to the efforts made to analyse and describe the vertical structure of the atmospheric boundary layer over different surfaces (cities, rural areas, complex terrain, water) as a prerequisite for trace gas and aerosol emission, transformation and dispersion studies.
The purpose of the "Tall wind project" is to improve the basis for design of large wind turbines by developing more reliable and accurate parameterisations of the wind profiles up to 400 meters height. Modern as well as future wind turbines will have hub heights above 100 metres with blades reaching 200 to 300 meters above ground. Reliable prediction of the wind profile in the lowest hundreds of meters in the atmosphere is therefore essential. A recent analysis of wind profiles at all heights up to 160 meters shows deviations of the wind profile above 80 meters the from the profile laws used so far near the surface. An important goal for the proposed project is to develop new practical and easy applicable recommendations for parameterizations of the wind profile aloft (above 50-80 meters height) in conjunction with recommendations for the measurements and instruments that can provide the necessary input for parameterizations. Recent research suggests that the wind profile above 50-80 meters height is influenced by both the surface conditions as well as the height of the boundary layer and the conditions at the top of the boundary layer. It also suggests that the parameterisation of the wind profile depends on the surface roughness in a new and not yet explored way, being different over the sea, in a rural areas and over a city/forest. An instrument package is suggested to study the wind profile and its dependence on processes at the top of the boundary layer. The instrument package will be deployed at the test station for wind turbines at Høvsøre at the west coast of Denmark, and at a meteorological site in Hamburg.
IMK-IFU contributed ceilometer and RASS measurements at Hamburg from spring 2011 to spring 2012. The data from these measurements were evaluated to determine MLH and the influence of the city of Hamburg on the vertical structure of the boundary layer. In this latter aspect the evaluation is closely link to other urban projects.
Danish Technical University, Wind Energy Institute, Risø Campus, Roskilde, Denmark, sveg∂risoe.dtu.dk, lead partner
NIMH, Sofia, Bulgaria
Hamburg University, Germany,
IMK-IFU of the Karlsruhe Institute of Technology, Garmisch-Partenkirchen, Germany
Vestas Wind Systems A/S, Denmark,
DONG Energy Power, Denmark
Danish Government, Danish Council for Strategic Research, Sagsnr. 2104-08-0025
2009 to 2013
Contact: Stefan Emeis