Towards spatially constrained gust models

The Science of Making Torque from Wind 2014

Bos, René^1 ; Bierbooms, Wim^1 ; Van Bussel, Gerard^1

Wind Energy Group, Faculty of Aerospace Engineering, Delft University of Technology, Kluyverweg 1, 2629 HS Delft, Netherlands^1

关键词: Computation time;    Computational burden;    Costs and benefits;    Load calculation;    Physical constraints;    Size and position;    Spatial dimension;    Turbulent structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/524/1/012107/pdf
DOI  :  10.1088/1742-6596/524/1/012107

来源: IOP

【 摘 要 】

With the trend of moving towards 10-20 MW turbines, rotor diameters are growing beyond the size of the largest turbulent structures in the atmospheric boundary layer. As a consequence, the fully uniform transients that are commonly used to predict extreme gust loads are losing their connection to reality and may lead to gross overdimensioning. More suiting would be to represent gusts by advecting air parcels and posing certain physical constraints on size and position. However, this would introduce several new degrees of freedom that significantly increase the computational burden of extreme load prediction. In an attempt to elaborate on the costs and benefits of such an approach, load calculations were done on the DTU 10 MW reference turbine where a single uniform gust shape was given various spatial dimensions with the transverse wavelength ranging up to twice the rotor diameter (357 m). The resulting loads displayed a very high spread, but remained well under the level of a uniform gust. Moving towards spatially constrained gust models would therefore yield far less conservative, though more realistic predictions at the cost of higher computation time.