Crack Detection in Turbo Rotors Vibrational Analysis and Fault Detection

Applying the theory of Lyapunov exponents for nonsmooth dynamical systems, chaotic motions and strange attractors are found in the case of a cracked rotor. To detect the crack and establish a clear relation between shaft cracks in turbo rotors and induced phenomena in vibrations measured in bearings, a model-based method is applied. Based on a fictitious model of the time behaviour of the nonlinearities, a state observer of an extended dynamical system is designed resulting in estimates of the nonlinear effects.