Showing papers by "Herman Van der Auweraer published in 1998"

Correlation of medium frequency test and fe models for a trimmed aircraft test section

Abstract: In the context of the European co-operative research project ASANCA II. methods for deriving a global vibro-acoustical model of the aircraft fuselage-cabin cavity system are investigated. Firstly, an extensive experimental study was performed on a trimmed SAAB 340 test section. A full frequency response function matrix was measured between a large number of structural and acoustical degrees of freedom. Based on these data, a non-parametric (vibro-acoustical principal field shape) system model was identified. Furthermore, a full FE model was derived for the SAAB 340 acoustic test section. First a model of the fuselage structure was formed and evaluated by means of eigenvalue analysis. Based on prior test results this model was updated. The remaining parts of the fuselage section, containing the cabin air cavity, trim panels and the material between the cabin structure and trim panels, was formed into a second model. This model was also analysed by means of eigenvalues followed by connecting the two (sub-) models, by means of modal coupling, to form the complete description of the cabin section. For this model, the frequency response functions were evaluated at the nodes corresponding to the experimental analysis. Finally, a correlation analysis between the FE and the test model was performed. Hereto, direct FRF correlation between the FE and test models, as well as a correlation of the principal field shapes corresponding to both data sets was executed.