Detection and assessment of the impact of turbulent humidity fluxes on turbulence in offshore wind parks

Project coordination:
Karlsruhe Institute of Technology (KIT), Institute of Meteorology and Climate Research, Atmospheric Environmental Research (IMK-IFU)

UL International GmbH (DEWI)

Duration of the project: 
08/2011 – 01/2015

It is the aim of the project to investigate the impact of atmospheric humidity and turbulent humidity fluxes on the static stability of the marine boundary layer in which future offshore wind parks will operate. Static stability influences vertical profiles of turbulence intensity and wind. Both these variables influence gain and fatigue of the wind turbines in these wind parks. Additionally, turbulence intensity determines the strength and length of wakes behind single turbines and entire wind parks,

Therefore, high-resolution humidity sensors are mounted at FINO1 parallel to the existing sonic anemometers. Lidar scanners for the detection of turbulence are mounted on some of the turbine nacelles as well.

Spectra and vertical turbulent humidity fluxes as well as their impact on turbulence and the static stability will be determined from the high-resolution wind and humidity measurements. The results can be used to check the turbulence parameterization schemes in numerical wind field models and to suggest and implement improvements for these parameterizations. The impact on wakes will be analyzed as well.

The results from these high-resolution measurements will provide a more reliable basis for the assessment of loads and fatigue of offshore wind turbines. The enhancement of numerical wind field and wake models allows for a better planning and operation of such wind parks. This contributes to a optimal integration of offshore wind parks into European electricity grids.