Helicopter Ground Resonance Phenomenon With Blade Stiffness Dissimilarities: Experimental and Theoretical Developments

Abstract : Recent works have studied ground resonance in helicopters under the aging or damage effects. Indeed, blade lead-lag stiffness may vary randomly with time and differ from blade to blade. The influence of stiffness dissimilarities between blades on the stability of the ground resonance phenomenon was determined through numerical investigations into the periodic equations of motion, treated using Floquet's theory. A stability chart highlights the appearance of new instability zones as a function of the perturbation introduced on the lead-lag stiffness of one blade. In order to validate the theoretical results, a new experimental setup was designed and developed. The ground resonance instabilities were investigated using different rotors and the boundaries of stability were determined. A good correlation between both theoretical and experimental results was obtained and the new instability zones, found in asymmetric rotors, were verified experimentally. The temporal responses of the measured signals highlighted the exponential divergence in the instability zones.
Complete list of metadatas

https://hal.archives-ouvertes.fr/hal-02180349
Contributor : Pierre Naegelen <>
Submitted on : Thursday, July 11, 2019 - 2:01:05 PM
Last modification on : Friday, January 10, 2020 - 9:09:48 PM

Identifiers

Citation

L. Sanches, Guilhem Michon, Alain Berlioz, Daniel Alazard. Helicopter Ground Resonance Phenomenon With Blade Stiffness Dissimilarities: Experimental and Theoretical Developments. J. Vib. Acoust, 2013, 135 (5), pp.051028--051028--7. ⟨10.1115/1.4024217⟩. ⟨hal-02180349⟩

Share

Metrics

Record views

34