Crack diagnosis for the shaft based on wavelet finite element method and genetic algorithm

The Rayleigh-Euler and Rayleigh-Timoshenko beam elements of B-spline wavelet on the interval (BSWI) are constructed to discrete slender shaft and stiffness disc respectively. Then the finite element model of rotor system is built up to solve the first three nature frequencies functions of relative crack location and depth by means of surface-fitting technique. Measured natural frequencies are used in a crack detection process and the relative crack location and depth can be identified through using genetic algorithm. The experimental results verify the validity of the method, which is feasible for practical application to diagnosis crack in rotor system.