Method for calculating irregular defect scattering sound field under action of rotation sound field

Abstract

The invention discloses a method for calculating an irregular defect scattering sound field under the action of a rotation sound field. Due to the fact that defects constantly change relative to the space position and postures of the sound field in the nondestructive testing process based on the rotation sound field, a traditional scattering sound field computing method has the defects that the calculation amount is large and the calculation process is complex, the irregular defect scattering sound field is hard to calculate. Therefore, a method that Kirchhoff approximation and the T matrix scattering numerical algorithm is combined to solve the scattering sound field is adopted, the scattering source method is introduced into the T matrix algorithm to solve the problem that convergence is hard to carry out when a T matrix is calculated for cracks, layering and other difficult non-spherical defects, and the convergence problem is solved. The efficiency of the overall detecting technology is taken into consideration, the dimension reduction processing is carried out on the scattering process through POD, and a finite dimension freedom degree system is used for approaching an original scattering model. By means of the method, the mechanism of the action of the irregular defects and the mechanism of the action of any rotation detecting sound field can be defined, the purpose of quantitative description can be achieved, and a most basic theory basis of the ultrasonic non-destruction testing study is achieved.

Description

technical field [0001] The invention belongs to the technical field of industrial ultrasonic nondestructive testing, and relates to a calculation method of an irregular defect scattering sound field under the action of a rotating sound field. Background technique [0002] As cylindrical parts or raw materials widely used in the fields of national economy and national defense construction, pipes, shafts and bars have always had a strong demand for non-destructive testing technology. Ultrasonic non-destructive testing technology has become the most widely used detection technology in the field of industrial non-destructive testing due to its incomparable advantages in terms of safety, applicability, automation capabilities, and richness of characteristic parameters. Through the full spiral scanning detection of the ultrasonic transducer array rotation and the linear motion of the object to be inspected, a global rotating ultrasonic field is generated. In terms of the completen...

AI Technical Summary

Problems solved by technology

In the non-destructive testing process based on the rotating sound field, the characteristics of the incident sound field are constantly changing with the movement, and the spatial position and attitude of the defect relative to the sound field are constantly changing. Continuously repeating the steps of setting the scattering calculation model, meshing and determining the initial boundary conditions, etc., brings about the problems of large amount of calculation and complex calculation process. In addition, in practical applications, there are many irregular defects, and the calculation efficiency of traditional methods will be more difficult to meet the application requirements.

In addition, in the scattering acoustic field analysis method aiming at solving the governing equation of elastic wave propagation, the defect scattering process is regarded as an operator that maps the incident detection acoustic field to the scattering acoustic field. Acoustically, this process can be equivalent to a The distributed parameter system with high dimensional freedom will further increase the degree of freedom of the distributed parameter system due to the introduction of the rotating sound field

From the overall perspective of detection technology, this high-dimensional distributed parameter system is bound to greatly reduce the efficiency of the follow-up process of the overall technology, including the calculation efficiency of steps such as rotation detection sound field optimization, reflection echo signal analysis, and quantitative inversion of defect characteristics.

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