대변형 보이론을 사용한 힌지없는 로우터 블레이드의 유한요소 공탄성 해석

Abstract

The coupled flap-lag-torsion aeroelastic stability of a hingeless rotor blade in hover is investigated using finite elements based on the large deflection beam theory. The stability boundary of the blade is calculated assuming blade motions to be small perturbation about the nonlinear steady equilibrium deflections which are obtained through an iterative Newton-Raphson method. The p-k method is used for modal flutter analysis based on coupled rotating natural modes. Various unsteady 2-dimensional strip theories are used to evaluated the aerodynamic loads. The sensitivity of the stability boundary to these aerodynamic assumptions is examined. Numerical results of the steady deflections and stability boundaries are presented for some representative blade configurations, and also compared with those given in the previous moderate deflection type theories.