METHOD FOR DETERMINING CONTACT CHARACTER OF BLADE OF ROTATING WHEEL WITH BODY OF TURBOMACHINE Russian patent published in 2018 - IPC G01M15/14 

FIELD: machine building.

SUBSTANCE: invention relates to the field of mechanical engineering, in particular turbine construction, and can be used for the development of aircraft engines in bench tests. Provide the wheel blade with at least one strain gauge sensor, provide the registration of the strain gauge signal, the signal level is monitored and, using a fast Fourier transform, the signal is processed in the vicinity of the point with the maximum signal level to obtain the values of the frequencies and amplitudes of the oscillations of the rotating wheel, the frequency of the oscillations of the wheel with the largest amplitude is chosen as the observable, then, representing the signal of the strain gage sensor at the observed frequency in the "amplitude-time" coordinates, monitor the periodicity of the signal and, in case of violation of its periodicity, fix the time range corresponding to the detected violation with the determination of the temporal coordinate of the violation of the periodicity of the signal, and then, in the above time range, the wavelet transformation of the signal is performed, making the transition from its representation in the "amplitude-time" coordinates to the representation of the strain gauge signal in the "frequency-time" coordinates, analyze the obtained picture of the signal and, from the form of the picture obtained, in the vicinity of the temporal coordinate of the violation of the periodicity of the signal, the nature of the contact of the blade with the body of the turbomachine is judged.

EFFECT: invention provides an increase in the reliability of detecting the presence and nature of the blade touching the turbomachine housing while reducing the time required for testing by continuously monitoring the moments of contact of the blades against the turbomachine housing.

1 cl, 6 dwg