Condition monitoring for aero-engine based on chaos exponents of dynamic system

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 correlation 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.