MEASUREMENT OF FLUID-STRUCTURE INTERACTION OF WIND TURBINES IN WIND TUNNEL EXPERIMENTS: CONCEPT AND FIRST RESULTS

Abstract. Fluid-structure interactions are crucial for the design of rotor blades of wind power systems. Up to now, the mutual interactions between rotor blades and turbulent wind flows have been treated by complex simulations or were observed at individual discrete points. In this paper, a measurement concept is presented where spatial information of the motion/deformation of a rotating wind turbine as well as the wind flow are recorded in wind tunnel experiments. Wind flow and motion behaviour are recorded simultaneously and contactless. Techniques from the field of photogrammetry and flow measurement techniques are combined, resulting in high demands on the measurement concept. Furthermore, solutions for the realisation of a common coordinate system as well as for the synchronisation of both measuring systems are presented. In addition, the validation of the entire measurement concept is carried out based on of some wind tunnel tests in which a single rotor blade is used for the moment. This showed that the measurement concept and the proposed solutions for the simultaneous recording of wind flows and rotor blade movements are suitable in principle and that movements can be recorded and reconstructed with high accuracy.