sin αst

LIST OF ATTACHMENTSSTRUCTURAL ANALYSIS OF BLADES
Loads
The blade loads are defined in the load cases of appendix A. They are repeated table E.9 for
easy reference:
154
Load case Blade
A
B
C
E
F
G
Table E.9: Loads applied to the model
The simplified and conservative load models consider the loads to be acting at the cross-
section by the airfoil root. Since the computational model is restrained in the same cross-
section the loads are applied as follows:
� Bending moments MyB and MxB are applied as forces at the blade tip. The value of
the forces FMyB and FMxB is equal to the moment divided by the distance from the
blade root to the blade tip.
� Normal forces FzB are applied as centrifugal loads that act at the mass centre of
the blade. To compensate for the removed blade hub junction, a remote mass of
0.450 kg is added to the blade root, causing correct positioning of the loads. The
rotational velocity is adjusted so that the correct values of the centrifugal loads
are achieved.
�F zB � 2.79 kN
�M xB � 33.1 N m
�M yB � 61.1 N m
MyB � 98.6 N m
MyB � 200 N m
FzB � 5.25 kN
MxB � 32.8 N m
MyB �
166 N m
When applying the loads in the above manner it is assumed that the moments are maximal
at the airfoil root and zero at the tip with, having a linear distribution.