In the field of aeroelastic analysis the reliability of modal data representing real structures is of crucial importance, as the employed aeroelastic solvers and the underlying physical phenomena is quite sensitive to the elastomechanical properties of the structure under investigation. Therefore it is necessary to be able to obtain reliable and repeatable experimental modal data from ground vibration tests (GVT). In this paper, it is proposed to support the results of an experimental modal analysis (EMA) on an aircraft, with a corresponding finite element model (FEM), in order to detect missing and/or local vibration modes, which could not be found experimentally with GVT methods. The FE model, parameterized in material properties as well as in section properties, is updated by an optimizer, which runs a hybrid constrained search algorithm to minimize an objective error function, until modal model from GVT and FEM match to a satisfactory degree. Such a model based ground vibration test methodology aims to supplement the test results for better quality and completeness. This aspect of FEM updating is also exploited in civil engineering field, especially for large structures where an ambient measurement with inherent uncertainties is the only option for data collection. The same principle methodology can also easily be applied to substructure modeling or automated mechanical design for any given design objective.
Model based ground vibration tests
Modellbasierte Bodenerschütterungstests
2009
10 Seiten, 7 Bilder, 2 Tabellen, 11 Quellen
Aufsatz (Konferenz)
Englisch
Automated nonlinearity detection in aircraft ground vibration tests
British Library Conference Proceedings | 1993
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