An Experimental Study of the Effects of a Nonlinear Store on the Steady-State Dynamics of a Test Airplane 2021-01-1117
Local nonlinearities can affect the global dynamics of their linear host structures. In the context of fixed-wing aircraft, failure of store mounting can result in strong local nonlinearities. In this work, we experimentally mimic store mounting failure conditions in a model airplane subject to harmonic excitation. Two identical stores are mounted under the wings and are placed symmetrically opposite each other. The configuration where both stores are “locked”, i.e., mounting is very stiff, serves as the baseline linear system. The second configuration involves unlocking one of the stores, enabling a geometrically nonlinear flexure connection between the unlocked store and the wing. The flexure lets the store interact with the first flexible mode of the airplane, resulting in large relative displacements between the store and wing. In addition, the configuration allows for vibro-impacts between the wing and store. Results show that the strong local vibro-impacts enable excitation of high-frequency modes unexcited in the baseline linear system. This is indicative of energy transfer from low to high frequency modes of the primary structure.
Citation: Copeland, T., Dalisay, J., Bergman, L., and Vakakis, A., "An Experimental Study of the Effects of a Nonlinear Store on the Steady-State Dynamics of a Test Airplane," SAE Int. J. Adv. & Curr. Prac. in Mobility 4(2):404-410, 2022, https://doi.org/10.4271/2021-01-1117. Download Citation
Author(s):
Timothy Copeland, Jon Dewitt Dalisay, Lawrence Bergman, Alexander Vakakis
Affiliated:
M+P International Inc., University of Illinois
Event:
Noise and Vibration Conference & Exhibition
e-ISSN:
2641-9645
Also in:
SAE International Journal of Advances and Current Practices in Mobility-V131-99EJ
Related Topics:
Fixed-wing aircraft
Aircraft
Mountings
Wings
Failure analysis
Research and development
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