Journal of Mechanical Science and Technology

The Korean Society of Mechanical Engineers (대한기계학회)
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Aeroelastic Stability Analysis of Hingeless Rotor Blades with Composite Flexures

  • Kim, Seung-Jo (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Kim, Ki-Tae (School of Mechanical and Aerospace Engineering, Seoul National University) ;
  • Jung, Sung-Nam (Department of Aerospace Engineering, Chonbuk National University)
  • Published : 2002.04.01
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Abstract

The flap-lag-torsion coupled aeroelastic behavior of a hingeless rotor blade with composite flexures in hovering flight has been investigated by using the finite element method. The quasisteady strip theory with dynamic inflow effects is used to obtain the aerodynamic loads acting on the blade. The governing differential equations of motion undergoing moderately large displacements and rotations are derived using the Hamilton's principle. The flexures used in the present model are composed of two composite plates which are rigidly attached together. The lead-lag flexure is located inboard of the flap flexure. A mixed warping model that combines the St. Versant torsion and the Vlasov torsion is developed to describe the twist behavior of the composite flexure. Numerical simulations are carried out to correlate the present results with experimental test data and also to identify the effects of structural couplings of the composite flexures on the aeroelastic stability of the blade. The prediction results agree well with other experimental data. The effects of elastic couplings such as pitch-flap, pitch-lag, and flap-lag couplings on the stability behavior of the composite blades are also investigated.

Keywords

References

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