Development of a high fidelity finite element model of a wind turbine blade via modal testing

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2015
Amer, Chadi
The design of an optimised horizontal axis 5-meter-long wind turbine rotor blade, is a research and development project, in order to fulfil the requirements of high efficiency torque-from-wind production. For this purpose, a research study is presented here, by investigating the structural characteristics of a composite wind turbine blade via finite element modelling and experimental modal analysis. At first, modal tests are performed by using various sensor-actuator pair combinations. After that the geometry was drawn via CATIA software. The materials are assigned as; two different types of glass fabrics, polymeric foam core material and steel-balsa wood combination and the finite element model of the blade was generated via MSC© PATRAN software with various meshes created on each structural part of the blade. MSC© NASTRAN was used as a solver for the dynamic analyses in order to obtain the natural frequencies and the corresponding mode shapes, namely; the first three out-of-plane bending, the first in-plane bending and the first torsional ones. Mesh independency check is also made before the analyses. In all analyses, the blade’s boundary conditions are set as free-free and fixed-free. Finally, the experimental modal analysis results are used to update the low fidelity model via FEMTools software in order to obtain a high fidelity finite element model of the wind turbine blade.