Numerical Substantiations on Aerodynamic Equivalence between Blade Flapping and Feathering Motions of a Lifting Rotor

摘要

To substantiate and aerodynamic equivalence between blade flapping and feathering motions which is used widely in trim and performance calculations of a helicopter, numerical study are carried out using the CFD code based on unsteady 3D compressible Euler equations with a moving grid system. Numerical calculations are conducted for a lifting rotor in hover and forward flight. By comparing unsteady aerodynamic loads on blade which execute pure flapping and feathering motions at various flight conditions, influences of unsteadiness due to blade motion and compressibility on the aerodynamic equivalence are clarified.