Future Concept Rotor Blade

The challenge

At present, rotor blade prototypes are tested by moving them separately both in and perpendicular to the direction of the wind in order to obtain information about how their material behaves over their 20-year service life more rapidly - this is a major simplification of how loads actually occur simultaneously in the field. As part of the “Future rotor blade concept” research project, scientists at Fraunhofer IWES are developing new methods that provide significantly more realistic data and allow a load-appropriate design to be produced.

The solution

Separating a blade into segments for testing - e.g. root segment and rotor blade tip - has two ad-vantages: Tests become possible at higher frequencies and with a more accurate load profile. The tests are rendered even more accurate when individual sections with a critically high load and greater material thickness or strong curvatures, for example, are investigated separately. This innovative approach not only produces more informative results, but also reduces the testing times by a calculated 30%, which means a notice-able cost saving.

At the conclusion of the first phase of the research project, which will take five years in total, the infrastructure will be operational and the test methods developed. A so-called hexapod test stand with a Reynolds platform to apply torsion forces and bending moments in parallel is being constructed. Manufacturers of rotor blades benefit from significantly shorter tests and particularly realistic load simulations, and their modified infrastructure set-up leads to lower energy costs as well.

The added value

From the overall perspective of the wind power industry, these test facilities play their part in reducing the energy production costs: When developers have a sure foundation on which they can employ greater creative freedom to develop a blade design opti-mised for efficiency and reliability, the economic efficiency of wind power utilization and thus its development potential increases.

This is an ERDF-funded project. More info: www.efre-bremen.de