Test Centers | Laboratories
Fraunhofer Institute for Wind Energy and Energy System Technology
- © Fraunhofer IWES
Rotor Blade Testing / Component Testing / Material Testing
Static and fatigue tests on full-scale rotor blades make it possible in a few months to predict the performance of a rotor blade, according to certification standards, over its 20 year life-span. Loads of up to 50 MNm are applied to rotor blades at various load points on a unique 70 m test stand. The application of the loads using hydraulic cylinders permits precise control of the loading. Fatigue testing is accomplished through cyclic loading at an eigenfrequency of the rotor blade, which provides an ideal load distribution along the blade. This is a fast testing method, with low energy consumption. Through measurement and frequency analyses, the rotor blade eigenfrequencies can be determined. Up to 250 strain gauges along with load cells, cable sensors, angle sensors and acceleration/temperature/humidity sensors provide a wealth of meaningful data.
In addition to the testing of full-scale rotor blades, the laboratory infrastructure consists of facilities for coupon and component testing, providing characteristic values for the evaluation and development of rotor blade substructures. For standard material characterization, uniaxial coupon test machines, 3 - 4 point bending jigs, antibuckling devices and a climate chamber are available. For structural characterization, an adaptable test bench of 12 m x 3 m with versatile loading capabilities, i.e. hydraulic cylinders up 100 kN and an excenter with 20 kN at 2 Hz, is utilized, e.g. for beam testing.