Detection method for double cross-hole pinch Lamb wave tomographic reconstruction system

Abstract

The invention discloses a detection method for a double cross-hole pinch Lamb wave tomographic reconstruction system. The detection method is characterized in that a projection data acquiring module (1) is connected with a projection data rearrangement module (2), the projection data rearrangement module is connected with a back projection module (3), the back projection module is connected with a filter module (4), and the filter module is connected with an image display module (5), wherein an energy transducer arranged according to a double cross-hole pinch structure of the projection data acquiring module (1) can perform projection scanning on defective areas to acquire projection data of Lamb wave; the projection data rearrangement module (2) rearranges projection data acquired by the double cross-hole pinch structure into parallel projection data; the differential and back projection module (3) performs back projection calculation on the parallel projection data in a space variation differential and an angle variation integration mode; and the filter module (4) performs finite Hilbert calculation on the back projection data to acquire reconstruction images of an object, and the reconstruction images are displayed through the image display module (5).

Description

technical field [0001] The invention relates to a detection method of a Lamb wave tomographic reconstruction system with a double-span distance, belonging to the field of ultrasonic non-destructive detection. It is suitable for nondestructive testing of thin plate structures in large equipment such as aerospace, bridges, oil pipelines, and large chemical storage tanks. Background technique [0002] Sheet structures are widely used in large chemical containers, aerospace, rail, bridge construction, dams, power equipment, and oil pipelines. The thin plate structure often introduces defects during processing, such as delamination, inclusions, hole shape defects, and crack defects, which will pose a threat to the safe use of equipment. At the same time, external loading and changes in the use environment during use can cause the expansion of internal small defect sources, and then cause fatigue damage. Therefore, it is urgent to carry out non-destructive testing to avoid accide...

AI Technical Summary

Problems solved by technology

Its disadvantage is that the reconstruction speed is slow and it is easy to converge to the solution closest to the initial value.

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