Fundamental aspects of fluid flow over complex terrain for wind energy applications

The flow over steep hills has been studied experimentally and numerically. The sinusoidally-shaped hills follow the parametric shape equations of the RUSHIL experiments. In the wind tunnel of the University of Kaiserslautern the flow over the hill was measured with the Laser Doppler Anemometry. Thereby, devices had to be found in order to thicken artificially the boundary layer. The numerical investigation has been carried out using several turbulence models comparing the calculated results with the experimental ones. In order to carry out reliable wind energy power predictions recommendations concerning numerical calculations are given.