ACOUSTIC
EMISSION & NDT SCIENTIFIC PUBLICATIONS
Acoustic Emission NDE of
a Wind Turbine Blade during Full - Scale Testing
Insight, Vol. 41, No
6, June 1999, pp. 366-368
Dr. Athanassios
Anastassopoulos, Dimitrios Kouroussis, Pantelis Vionis,
Vassilios Kolovos
The use of
Renewable Energy Sources has rapidly increased in the
European Community, during the last years. Particularly in
Greece, the high Wind Energy potential favours the
installation and use of Wind Turbines. As a result, it has
become necessary to find an effective NDT method for the
structural integrity assessment of W/T blades, which are the
most vulnerable W/T parts. The present paper is a brief
summary of the results of Non-Destructive Evaluation of a
new, 12m Wind Turbine Blade made of FRP, using the Acoustic
Emission technique, during controlled, static and fatigue
stimulation. The test was carried out at the Centre for
Renewable Energy Sources, in Athens and data analysis was
performed by Envirocoustics ABEE. The AE technique revealed
that the maximum chord area was a critical area of the
blade, before any damage had become apparent, from the
first, already static loading. Fatigue test results verified
the existence of flaws in the critical area pointed out by
the first static loading. Follow-up visual inspection
revealed a 20cm long crack at the trailing edge of the blade
at the maximum chord area which first became visible after
several thousands of fatigue cycles had occurred between the
two tests.