1997 年 45 巻 525 号 p. 575-583
The cross coupling effects of a helicopter rotor in low advance ratio are experimentally studied using the Dynamic Running Test Facility which was built at National Defense Academy recently. Design features and basic performances of the facility are briefly described. Flapping motions of the model rotor blade are precisely measured together with its thrust and torque characteristics at various combinations of test parameters. It is clarified that nonlinear behavior of the cross coupling effects on the advance ratio are attributed to the phase shift properties of blade flapping motions due to nonuniformity of induced velocity distributions on the rotor disc. Usefulness of a dynamic running test is also ascertained for accurate measurements of aerodynamic and dynamic phenomena of a rotorcraft in low speed flight.