Stability of nonuniform rotor blades in hover using a mixed formulation

摘要: Abstract : A mixed formulation for calculating static equilibrium and stability eigenvalues of nonuniform rotor blades in hover is presented. The equations are nonlinear solved by an accurate efficient collocation method. linearized perturbation a one-step, second-order integration scheme. numerical results correlate very well with published from nearly identical analysis based on displacement formulation. Slight differences the traced to terms that relate moments derivatives rotations. With present ordering scheme, which order squares rotations neglected respect unity, it not possible achieve completely equivalent models formulations. study one-step methods reveals Taylor expansion necessary good convergence rotating blades. Numerical hypothetical blade, including solution, were obtained no more effort or computer time than required uniform blade analysis. (Author)