Press Release
____________________________________
IABG develops accelerated method for dynamic rotor
blade testing
Ottobrunn, 15 Sep. 2015. IABG has developed a new, considerably
improved method for dynamic fatigue testing rotor blades over the prior art
that offers significant advantages on existing test methods.
The fatigue strength of rotor blades must be proven to certify wind energy
plants. As a rule, this verification comprises over several million load
cycles; i.e. by vibration testing rotor blades subject to the resonance
principle.
The test frequency is hereby limited by the test item’s natural initial bending
frequency, which – for current blades – is well under one Hertz, causing
long test durations and high costs. In addition to that, the blade’s bend line
that occurs from areodynamic loads in real operation often deviates from
the bend line of its initial natural mode during resonance testing. This can
lead to local hypo or hyper loads and thus considerably influences the test
quality.
The standard to avoid this is to approximate the bend line to real operating
conditions by attaching auxiliary masses during testing. However, this
decreases the natural frequency and leads to even longer test durations.
Due the systemic setup, the test is furthermore carried out in a consistent
central position and thus cannot not reproduce the variable wind-depended
mean loads occurring in real operation.
The improved test method developed by IABG allows for significantly
reducing or avoiding these disadvantages. The method facilitates an
increase of the natural bend mode, optimising the bend line, as well as
adapting the mean load during testing.
The patent for the testing method has in the meantime been granted by the
German Patent and Trade Mark Office. In the context of an application
example using a real rotor blade it could be shown that IABG’s new method
is suited to double the testing frequency while reproducing the desired bend
line occurring in real operation at the same time.
As early as in the nineteen-eighties, IABG was able to successfully test the
rotor blade of the GROWIAN wind energy plant based on its many years of
experience in testing aircraft wings. Thanks to its expertise from various
high technology markets, IABG supports leading manufacturers of wind
energy plants in terms of method development, as well as in verification by
calculation and testing.
IABG mbH
Einsteinstrasse
20
IABG ltd.
85521
Ottobrunn
Einstein route 2085521
GERMANY
Ottobrunn
Your
Theircontact:
partner:Monika Peter
Monika
chief Peters
Head
of Corporate
enterprise
communication
Communications
Tel. 089 6088-2030Fax
Tel.
+49
89 6088-2030
089
6088-4000mobil
Fax
+49
89 6088-4000
0171 7359565
Mobile 0171 7359565
Email
Email
petersm@iabg.de
petersm@iabg.deInternet
Internet
www.iabg.de
www.iabg.de
Page 1
Press Release
____________________________________
About IABG
We are a closely networked business group and offer integrated, futureoriented solutions in the sectors Automotive • InfoCom • Mobility, Energy &
Environment • Aeronautics • Space • Defence & Security. We understand
the requirements of our customers and support them independently and
competently. We implement effectively, efficiently and with target
orientation. We operate reliably and sustainably. Our international market
presence and our success are based on technological excellence and a fair
relationship to our customers and business partners.
Page 2