System identification and experiment evaluation of a piezoelectric-based sting damper in a transonic wind tunnel

In wind tunnel tests, a long cantilever sting is usually used to support the test model. However, it is vulnerable to violent oscillation without an effective damping device. In this paper, a piezoelectric-based sting damper designed for solving the vibration problem in wind tunnel tests is detailed, especially its system identification process, which is generally a difficult challenge in practice. Besides, a new hardware platform for various instruments is established and a real-time control software system is built to verify the feasibility and practicability of the whole vibration control process. Furthermore, aiming at measuring the suppression of the first two order's vibration, the impulse stimulus test as well as the transonic wind tunnel test are carried out to evaluate the capability of the sting damper. The results show the excellent performance of the Zoom-frequency response function algorithm in identifying the damper, based on which suitable parameters of PD controller are acquired and the damping coefficient of the sting increases over 60 times in impulse stimulus. In addition, the superiority of the sting damper in suppressing vibration is proved by the transonic wind tunnel test, in which the maximum testing angle of attack enlarges under different Mach numbers.