Location of Crack Faults of Hydraulic Pipelines Based on Nonlinear Output Frequency Response Function

A novel method is proposed for locating crack faults of hydraulic pipelines based on Nonlinear Output Frequency Response Function (NOFRF). The NOFRF are a series of one-dimensional functions of frequency, which recently proposed facilitating the analysis of nonlinear systems in the frequency domain. Developing from nonlinear system Volterra series, it has capability for the nonlinear link of hydraulic pipelines crack fault diagnosis. In this new method, the crack location is confirmed by the value of NOFRF, which is obtained from the gathered vibration signal. The numerical results clearly show that the proposed method can locate the crack fault with good accuracy.