Aviation
Enterprises Ltd has, since 2002 been developing a wealth of experience in
design and manufacture of Tidal Turbine (TT) blades. As a result of this
momentum, and interest expressed in our capabilities by other UK tidal
turbine developers, AEL decided, in 2005, to apply its expertise and develop
this business to provide a specialist composite TT blade design, development
and manufacture service, focussing R&D on reliable design, efficient use of
materials and minimising development and production costs.
In particular by;
Effective
materials selection and establishment of a comprehensive materials database.
Manufacturers’
data is rarely considered definitive and necessitates independent testing.
Research
into the effects of long-term immersion in seawater, something that is a
relatively new requirement.
The
review of adhesives and surface preparation techniques. Again, reference
material for previous work is unlikely to be available.
Investigating and meeting the standards and safety factors applied by the Certification Authorities.
Investment in our own suite of numerical tools and production and tooling equipment to minimise costs.
Certification Authorities, without adequate and
reliable data, will always tend to the conservative and, even then,
particularly in the case of design details, without specific testing,
fatigue life is extremely difficult to predict.
AEL has experience of working with both DNV & GL and DNV is currently
overseeing the AEL R&D programme to ensure acceptable standards are used and
reliable data is developed.
These programmes will accelerate the technology, minimise R &
D further expenditure on background testing and minimise the capital cost of
blade development providing reliable data to ensure that fatigue life is
achieved, and scheduled and unscheduled maintenance minimised.
As the data base and confidence in the material performance grows so higher strain allowables will be accepted, leading to the design lower t/c ratio blades which may exhibit lower cavitation losses, and - in turn - permit higher rotational speeds with attendant savings in the power train capital cost and/or the ability to run faster and, therefore, with improved efficiency.