Dispersion curves applied to the propagation of guided waves in structures of hollow circular section

Abstract

The use of long tubular structures, such as fluid transmission pipes or structural support (civil area), are common in many industries (oil, petrochemical, power plants). These structures must guarantee reliability and absence of defects, requiring an adequate inspection method to ensure this.

Its inspection, using conventional non-destructive tests, is expensive, difficult and sometimes impossible due to its length, inaccessibility to complete structures and dependence on the exact evaluation of defects; This is why many researchers consider the use of guided waves as an inspection method because it allows the use of waves with different properties for the detection of defects.

These waves provide an attractive solution to this problem because they can be excited in one place in the structure and travel many meters. However, this method is made difficult by the presence of many possible wave modes, the majority being dispersive.

In the present work, the characteristics of guided wave propagation in metallic structures of hollow circular section are studied, calculating the dispersion curves obtained by two work methodologies using finite elements, obtaining dispersion curves for a cylindrical section.

Keywords: guided waves, nondestructive testing, dispersion curves.