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OutlineBasics of wind turbine bladeBlade element theoryMembrane & plate bending modelShell element in FEMANSYS model
Membrane & plate bending3D structures under arbitrary loads
Split element into two types for different calculations
Membrane element for in-plane loads
Plate bending elements for transverse loads and bending
Bending element analysis
Tranverse displacements and rotations are taken as degrees of freedom.◦
◦ are 4x4 matrices
FEM for shell analysisA combination of a plate bending and membrane element
The DOF of a plate and plane stress finite element in a local element-aligned coordinate system are considered
Displacement model The displacement model for the flat shell is expressed as
Ni is the bilinear shape functions associated to node i,
and
Linear system Combining simultaneously membrane and bending actions, a linear system for the vector of nodal unknowns q can be written
where ke is the stiffness matrix composed of membrane and plate stiffness element matrices
Deformation & stress contours
More stress at the blade root
Thicker material closer to root to endure high loads
(Displacement contour)
(Stress contour)
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