دانلود Vibration Reduction of a Bearingless Helicopter Rotor with Composite Tailored Couplings

Abstract

The  study  was  conducted  to  gain  some  important  characteristics  of  the  influence  of  the  blade  flap-bending/torsion  elastic coupling stiffness on blade root flap-shear force and vibratory hub loads of a bearingless rotor. Based on the aerodynamic force,  this  paper  presents  a  loose  coupled  aeroelastic  analytical  model  by  finite  element  method.  Four  sets  of  composite  rotor  with different  elastic  couplings  were  designed  and  investigated.  The  results  of  the  investigation  showed  that  flap-bending/torsion couplings  have  a  significant  effect  on  the  rotor  vibratory  hub  loads  and  the  distribution  of  the  couplings  also  critical  for  the degree of vibration reduction. Through the present research, it has been demonstrated that structural couplings can significantly impact rotor vibration characteristics.