Crack near-field deformation analysis area determination method based on level set method

Abstract

The invention discloses a crack near-field deformation analysis area determination method based on a level set method. The method comprises the following steps of 1) setting a crack near-field initial analysis area; 2) obtaining a coordinate position of a crack propagation track; 3) calculating a level set function of the crack propagation track; 4) updating an analysis area; (5) repeating the steps (2)-(4), and continuously updating the analysis area according to the expansion information of the crack so as to complete the crack near-field analysis area adaption. According to the method, the crack near-field deformation analysis area of the element and the structural member can be rapidly determined under the crack propagation condition, the manual determination of the crack near-field analysis area can be avoided, the introduction of errors by testers in the implementation process is effectively avoided, and the accuracy and the reliability of the crack near-field deformation analysis area are improved; secondly, the analysis efficiency is high, and the updating of a crack near-field analysis area can be rapidly completed; and finally, the labor cost can be reduced, the automation of the crack near-field deformation analysis area is realized, and the damage tolerance test technology is improved.

Description

technical field

[0001] The invention relates to the technical field of damage tolerance in crack growth tests, in particular to a method for determining a crack near-field deformation analysis region based on a level set method. Background technique

[0002] The deformation analysis in the near field of the crack is realized based on the digital image correlation method. The initiation and expansion of the crack cause a strong discontinuity in the analysis area, and the gap formed by the crack causes the pixel information in the collected image to change. The pixel information of the gap part It will cause errors in deformation analysis. Therefore, it is necessary to remove the analysis region (Region of Interest, ROI) at the beginning of the analysis. As the crack expands, the analysis region needs to be updated accordingly. In the crack growth test, it is necessary to take a large number of photos of the cracks. If the analysis area is manually updated, it will affect the ...

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