FEM analysis of circumferential wave propagation within thin-walled pipes for detecting axial flaws

摘要

Circumferential wave propagation in thin-walled pipes excited by an angle beam transducer has been analyzed by an explicit finite element method. The simulation results show that the wave energy does not propagate along the straight path predicted by (he ray theory, but it is propagated macroscopically along the circumference. The amplitude peak within the pipe wall changes with time on a certain cross section, which means the energy is redistributed with time. The radial position of the maximum energy varies within the middle section of about 60% thickness for various sections and deviates greatly from the prediction by ray theory.