Crack Detection using Non-linear and Dissipative Acoustics

A theoretical model for identification of acoustical non-linearity using Burger’s equation was implemented in a MATLAB program. The program identified both the non-linearity parameter and the distance from the signal source. Tests were performed in order to verify the theories. Tests with a steel bar showed no detectable non-linearity, probably due to insufficient wave amplitude by the signal source. A crack model was made with successful result.

Contents

1 Notation
2 Introduction
2.1 Non-Linear Acoustics
3 Method of Non-linear analysis
4 Theoretical Model
4.1 Calculation of Reference Fourier-coefficients
4.2 The analysis
5 Application of Theoretical Model in MATLAB
6 Test phase
6.1 Test Equipment
6.2 Test Procedures
6.2.1 One Input Frequency
6.2.2 Two Input Frequencies
6.3 Test set-up
6.4 Test results
7 Discussion
8 Conclusions
9 References

Author: Daniel Carldén, Daniel Thuresson

Source: Blekinge Institute of Technology

Reference URL 1: Visit Now

Leave a Comment