Parameter Identification of Crack Growth in Helicopter Blade

Abstract:

This paper presents a fatigue parameter identification analysis and response of a cracked helicopter blade in the hovering flight condition reinforced by GFRP fiber. The search for increasingly high performances in the field of the helicopters brings to the development of materials having higher rigidities and specific resistances. The use of the composite material offers a good aeroelastic Stability. On the basis of aerodynamic model, the use of the finite element method makes it possible to develop a three dimensional model of the blade and to establish dynamic equations of the movement. Numerical calculations of the model developed, prove that the Eigen frequencies of helicopter blade were decreased after cracking in the critical zone, and this reduce is nonlinear; however the stress increased with crack propagation. Therefore the modal parameter identification is an important factor for the detection of fatigue in aircraft structures.

• Periodical: Key Engineering Materials (Volumes 577-578)
• Pages: 673-676
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.577-578.673
• Online since: September 2013
• Authors: A. Chellil, A. Nour, S. Lecheb, M. Chibani, H. Kebir
• Keywords: Aeroelastic, Blade, Composite, Crack, Fatigue, Stability

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