亚跨风洞中舵面亚临界颤振试验

设计了舵面颤振试验装置，在亚跨超风洞中对展弦比2．0的NACA0012矩形舵面开展了颤振试验研究。试验马赫数范围为0．3～0．75。试验采用直接观测法获得舵面在不同质量特性条件下的亚声速和接近跨声速的颤振特性。同时还采用亚临界数据分析方法对试验的扭转应变信号进行了离线分析，即通过采用ARMA方法识别扭转应变信号的阻尼和频率，并通过阻尼外插得到颤振临界动压值。研究结果表明：该试验装置可以用于在现有亚跨超风洞中开展舵面颤振问题研究。当采集的亚临界信号为典型指数衰减信号时，以ARMA方法为基础的亚临界颤振试验技术可以稳定地识别出信号阻尼和频率，并较为准确地获得舵面的颤振临界动压、颤振频率等颤振参数。

Flutter test of rudder in sub-tran-supersonic wind tunnel using subcritical response methods

A testing apparatus for conducting rudder flutter research in a trisonic wind tunnel has been developed. A NACA0012 rectangular ruder with aspect ratio 2.0,mounted on the testing apparatus,was tested in a trisonic wind tunnel over a Mach number range of 0.3-0.75. The subsonic and transonic flutter characteristics of the rudder with different mass properties were obtained by slowly increasing the dynamic pressure until flutter actually occurs. Some flutter onset conditions were established from extrapolated subcritical response measurements. Base on the ARMA method,the subcritical response method was used to identify damping and frequency of the response signal. The experimental results show that the wind tunnel flutter testing apparatus can be employed to investigate aeroelastic behavior of rudders in trisonic wind tunnel. The subcritical response method based on ARMA method can identify the damping and frequency of the response signal when the subcritical response signal was a typical exponential damping signal. And the flutter onset conditions can accurately be extrapolated.