Ground Vibration Testing; Nonlinearity; System Identification
Abstract :
[en] The nonlinear resonant decay method identifies a nonlinear dynamic system using a model based in linear modal space comprising the underlying linear system and a small number of additional terms that represent the nonlinear behavior. In this work, the method is applied to an aircraftlike wing/store/pylon experimental structure that consists of a rectangular wing with two stores suspended beneath it by means of nonlinear pylons with a nominally hardening characteristic in the store rotation degree of freedom. The nonlinear resonant decay method is applied to the system using multishaker excitation. The resulting identified mathematical model features five modes, two of which are strongly nonlinear, one is mildly nonlinear, and two are completely linear. The restoring force surfaces obtained from the mathematical model are in close agreement with those measured from the system. This experimental application of the nonlinear resonant decay method indicates that the method could be suitable for the identification of nonlinear models of aircraft in ground vibration testing.
Disciplines :
Aerospace & aeronautics engineering
Author, co-author :
Platten, M. F.; Romax Technology > NVH Team
Wright, J. R.; University of Manchester > School of Mechanical Aerospace and Civil Engineering
Cooper, J. E.; University of Liverpool > Department of Engineering
Dimitriadis, Grigorios ; Université de Liège - ULiège > Département d'aérospatiale et mécanique > Intéractions fluide structure et aérodynamique expérimentale
Language :
English
Title :
Identification of a Nonlinear Wing Structure Using an Extended Modal Model
Publication date :
2009
Journal title :
Journal of Aircraft
ISSN :
0021-8669
eISSN :
1533-3868
Publisher :
American Institute of Aeronautics and Astronautics
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