摘要
从混沌理论、分形学的角度研究了航空发动机失稳工作,计算了发动机失稳过程系统混沌特征量的变化.采用小波降噪对压气机压力数据作预处理,重构了系统相空间,改进了关联积分的计算方法,在此基础上采用滑动窗口方法计算了发动机失稳过程中系统李雅普诺夫指数、关联维数的变化.计算结果显示,发动机失稳过程中系统的混沌指数有显著的改变,系统进入失稳状态李雅普诺夫指数增大0.19,而关联维数则减小0.45,表明混沌指数可用于发动机系统的状态监控,亦为发动机失稳运动的特性研究提供了新思路.
The instability condition of aeroengine was studied in light of chaos and fractal theories, the chaotic character exponents of aeroengine in the process of entering instability condition were calculated. First, the pressure signal was denoised with wavelet method, and then the phase space of the engine was reconstructed. The method to calculate correla tion integral was improved, then, the Lyapunov exponents and correlation dimension were calculated with the method of sliding window. The results show that the chaos exponents changed markedly as the condition of aero-engine varies, as a consequence, the chaos exponents can be used to identify the aero engine condition and as a new method to study the dynamic characteristics.
出处
《航空动力学报》
EI
CAS
CSCD
北大核心
2008年第11期2133-2136,共4页
Journal of Aerospace Power
关键词
状态监测
李雅普诺夫指数
分形维数
condition monitoring
Lyapunov exponent
fractal dimension
