Development of high frequency dynamic test system for rotor airfoil in subsonic wind tunnel

Rotor is the driving force source of the helicopter, and the airfoil is the key to affect the rotor performance. In order to satisfy the demand of test simulation for the optimal design and performance determination of advanced helicopter rotor airfoil in wind tunnel, a high frequency dynamic test system for rotor airfoil is developed in FL-54 subsonic wind tunnel which belongs to the AVIC Aerodynamics Research Institute. The hydraulic motor with hydrostatic support seal is used to design the drive system. With the zero-friction characteristic of hydrostatic support seal, high control precision and high dynamic motion index are the notable features of the system. Based on the compound feedforward + PID control, an amplitude/phase adaptive compensation control algorithm is designed to automatically track the amplitude and phase of the sinusoidal motion until it coincides with the command curve. This test system can achieve an airfoil dynamic test capability with the maximum wind speed of 0.6Ma, the highest test frequency of 70Hz (at the amplitude of 5°). The airfoil standard model is used to verify the system performance index and the accuracy of airfoil dynamic test data. The verification results show that the system performance index and test data accuracy meet the design requirements, and can provide a wind tunnel dynamic test platform for advanced airfoil development.