• wind turbine
• CFD

This degree thesis is part of the studies on wind energy.
The company that has proposed this work is the XEMC Darwind.
Darwind’s operations have been fully integrated with those of XEMC WINDPOWER.
XEMC Darwind is developing a unique, top-down bottom-up, 5 MW offshore, Direct Drive
Permanent Magnet wind turbine generator with a diameter of 115 meters at 90
meters hub height. The XD115 wind turbine is in fact heir to the Dutch wind energy and
offshore tradition.
XEMC Darwind believes that offshore locations require ad hoc sealed and
robust technology, designed for low cost installation, logistics and low cost maintenance &
service throughout the lifetime of the turbine. This degree thesis becomes part of this project in
relation to the interaction between the flows of air between the inside and the outside of the LM 55.4 P blade.
The rotation in blade is too high, about 18 rpm. This is the difference between Darwind’s
turbine and the others companies. This means that the blade is subject to high centrifugal force. For this force inside the blade builds up a pressure gradient from
the bulkhead to the tip. Our studies investigate if this gradient is dangerous for the
blade in term of static resistance of the bulkhead and if there is a leakage and where is
that leakage. Because the position of leak is important for the pressure gradient.

The work is developed in the follow point.

• Preliminary studies of bulkhead pressure in different situation.
• Studies of drain holes resistance
• Studies of diffuser resistance
• Experimental test in Hammelev, Denmark
• Elaboration of experimental data and estimation of leakage
• CFD simulation of blade in operative conditions