CFES and MANE Special Seminar
Wednesday, December 8, 2010
Location: Darrin Communications Center - DCC 337
Time: 10:30 – 11:30AM
Lidar Measurements for Wind Energy
Dr. Jakob Mann
Riso National Laboratory for Sustainable Energy, Technical University of Denmark
Host: Dr. Luciano Castillo (MANE)
Wind lidars (light detection and ranging) have manifested themselves as powerful tools to measure the mean wind
over flat terrain for wind resource estimation. They can essentially replace meteorological towers for that purpose, but
there are many additional opportunities for lidars in wind energy research. It would be advantageous if lidars could be
used to give reliable information on turbulence intensity, which would increase their usefulness as tools for wind
turbine sitting. The main problem with that is the spatial averaging of the turbulent wind field, which is carefully
studied experimentally and explained theoretically through application of the spectral velocity tensor. Different ways
of analyzing the lidar data produce very different attenuation of the statistics depending on how the information from
the various beams is combined. In addition, lidars mounted on the nacelles, blades or hubs of turbines bear promise of
more efficient turbine control for improved power production and reduced mechanical loading due to wind gusts. This
last opportunity requires detailed investigation of Taylor's frozen turbulence hypothesis. Finally, several lidars will be
combined to produce a "wind scanner" which can be used to scan the three-dimensional wind flow around terrain
features, or a wind turbine as well as other relevant atmospheric flows.
Dr. Jakob Mann, Research Professor at the Riso DTU
1994 PhD. from Aalborg University
1990 MSc. from Aarhus University in Astrophysics
1987 BSc. from Aarhus University in Mathematics and Physics
Key Research Topics:
- Modeling of atmospheric turbulence, extreme winds and wind profiles for wind turbine load calculations and wind
resource estimation.
- Application of laser Doppler techniques for energy research
- Experimental investigations of Lagrangian properties of turbulence and their application in dispersion modeling.
Other:
Co-PI on a DSF Research Center on flow modeling for wind energy
Research Leader for Wind Power Meteorology