Static Stability Derivatives in Pitch and Roll of a Model Circulation Control Rotor.

摘要

Static stability derivatives of a circulation control rotor (CCR) were obtained from wind tunnel evaluation of a model rotor. The derivatives show general characteristics similar to those of a conventional rotor in the advance ratio range 0.20 < or = mu < or = 0.30. The conventional characteristic of a destabilizing static-speed-stability term for hingeless rotors appears to be magnified for low advance ratios in the CCR system. At higher advance ratios the static-speed-stability term becomes neutral and then strongly stable for CCR. Other derivatives show the same tendency toward neutral stability as speed is increased beyond an advance ratio of 0.30. If this model trait is corroborated by future full-scale CCR evaluation, it will represent a significant advantage in stability characteristics over current hingeless rotors. (Author)