EXPERIMENTAL CONFIRMATION OF LIMIT CYCLE OSCILLATION FOR ACTIVE CONTROL OF TRANSONIC FLUTTER IN WIND TUNNEL

摘要

The wind tunnel test was carried out with great care obtaining successfully limited numbers of LCO data at dynamic pressures above the open loop flutter point. After confirming a flutter dynamic pressure of the controlled wing, we tried to excite the wing by a leading edge control surface oscillation at three different dynamic pressures in between the open and the closed loop flutter dynamic pressure. Even though the control might have lost the effectiveness due to large amplitude of LCO and resulting amplitude might have broken the wing seriously, we have succeeded in getting smaller amplitude of LCO. Adjusting the mathematical model to new wind tunnel test data, the model could predict the closed loop bifurcation that shows good correspondence to the test data.