FLUTTER BOUNDARY PREDICTION OF TURBULENCE EXCITATION RESPONSE BASED ON RANDOM DECREMENT METHOD

A flutter boundary prediction technique is developed upon turbulence excitation response of wind tunnel flutter tests. Firstly the random decrement method is employed to extract the system's free decaying signal from the turbulence excitation response. Then main modal parameters, which are needed to establish the stability criterions, are identified through the matrix pencil method. Eventually, a curve fitting about variation of the criterion with dynamic pressure or velocity is plotted to extrapolate the flutter boundary. The simulated and wind tunnel test results show that: the modal parameters of turbulence excitation response can be identified precisely through the method of random decrement and matrix pencil, and the stability criterions have a clear downward trend so that it will be very helpful for advanced prediction of flutter boundary and the reduction of potential risk during flutter tests.