Method and device for fatigue test crack diagnosis of engine body

Abstract

An embodiment of the invention discloses a method and a device for fatigue test crack diagnosis of an engine body. A strain foil and an acceleration transducer respectively collect strain signals and vibration signals of the engine body in a fatigue test. A data collection card converts the strain signals and the vibration signals respectively into digital signals and transmits the strain signals and the vibration signals which are converted into the digital signals to an industrial personal machine. The industrial personal machine collects a plurality of discrete signals from the strain signals and the vibration signals which are converted into the digital signals, conducts wavelet analysis on the plurality of collected strain signals, conducts signal singularity monitoring on analysis results, conducts Fourier transform on the plurality of collected discrete vibration signals and conducts characteristic value analysis on conversion results. The industrial personal machine judges whether results of singularity monitoring and characteristic value analysis are abnormal or not and judges that an engine has fatigue cracks on yes judgment. The method and the device can reduce unnecessary manpower and financial resources.

Description

technical field

[0001] The invention relates to the field of test diagnosis, in particular to a method and device for diagnosing a fatigue test crack of an engine body. Background technique

[0002] For the engine, fatigue refers to the process of forming cracks or breaking after a certain number of cycles due to local permanent structural changes at certain points or points under the action of cyclic stress or cyclic strain.

[0003] In the existing engine body fatigue tests, the diagnosis of fatigue cracks in the engine body is generally observed manually with the naked eye. When fatigue cracks are found, sometimes the cracks have expanded to a large size, resulting in very inaccurate test data; and if the cracks are not found in time, it may cause test accidents.

[0004] In the existing body fatigue test, there is no special method for diagnosing the fatigue cracks of the body to realize the automatic shutdown of the machine. In the actual test, it is necessary to have...

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