sin αst

The applied loads are illustrated on figure E.4.
Figure E.4: Model loads
STRUCTURAL ANALYSIS OF BLADES
The bending forces at the blade tip are applied at a point, which is a projection of the cen-
troid of the airfoil root. This ensures that the applied forces produce root bending mo-
ments that are equivalent to those of the load cases. The tip forces originating from MyB
and MxB are aligned parallel and perpendicular to the rotor axis, respectively. The centrifu-
gal loads are applied with reference to the rotor axis.
The following sections show six stress plots of each of the load cases. The upper view on
each figure shows the downwind part of the blade and the lower view shows the upwind
surface, which faces the incoming wind. All reported stresses are in MPa. Each section
concludes with a summary of the stresses and a validation of the limit states.
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