Using High-Resolution Measurements to Update Finite Element Substructure Models

Many methods have been proposed for updating finite element matrices using experimentally derived modal parameters. By using these methods, a finite element model can be made to exactly match the experiment. These techniques have not achieved widespread use in finite element modeling because they introduce non-physical matrices. Recently, Scanning Laser Doppler Vibrometery (SLDV) has enabled finer measurement point resolution and more accurate measurement point placement with no mass loading compared to traditional accelerometer or roving hammer tests. Therefore, it is worth reinvestigating these updating procedures with high-resolution data inputs to determine if they are able to produce finite element models that are suitable for substructuring. A rough finite element model of an Ampair Wind Turbine Blade was created, and a SLDV measurement was performed that measured three-dimensional data at every node on one surface of the blade. This data was used to update the finite element model so that it exactly matched test data. A simple substructuring example of fixing the base of the blade was performed and compared to previously measured fixed-base data.