Signal Source Localization Method For Metal Fatigue Damage Based On Z Shaped Array

In recent years,with the rapid development of industry,the use of steel has increased year by year,and the fatigue fracture of steel structure has become an unavoidable problem.Under prolonged use,metals are prone to fatigue damage,resulting in huge losses.Because the fatigue fracture of metal is a sudden event after long-term damage accumulation,it is difficult to realize long-term monitoring and detection by conventional nondestructive testing based on static testing.The use of acoustic emission technology can quickly detect the production of fatigue fracture and quickly locate the damage,thus reducing the loss caused by fatigue fracture.In order to locate the position of fatigue fracture quickly,the acoustic emission source localization method based on trigonometric time difference method is proposed.On the basis of this localization method,the acoustic emission source localization method of Z shaped array is proposed.The localization method is not limited by the anisotropy of the material,does not need to know the sound velocity distribution in the material,only needs to deal with the sound signals received by the four sensors of the Z shaped array,and the time difference of the signal can be obtained,and the location of the acoustic emission source can be quickly calculated.The utility model has the advantages of less number of sensors,simple operation,strong applicability and small space occupation.In order to verify the positioning effect,the whole process of acoustic emission localization is verified by simulation experiments,and noise reduction is carried out by the singular value noise reduction method based on SVD.The denoising method starts with the angle of matrix,and preserves the singular value of the required signal,and returns the effect of noise reduction by the singular value of the zero noise signal.It has good noise reduction effect for chaotic noise,simple operation,less resources and wide space for use.The experiment shows that the acoustic emission of "Z" array based on trigonometric time difference method based on the SVD singular value noise reduction can quickly and accurately calculate the position of metal fatigue fracture,which is of great significance to the rapid treatment of metal fatigue fracture and reduction of economic loss.