Numerical study on two circle void flaws in cylinders

In this article, three-dimensional Kirchhoff inverse scattering method is modified to convenient form for a cylindrical specimen that includes three-dimensional defects including two-circle voids. Ultrasonic measurements are carried out. The measurement area in the modified methods is restricted in the plane perpendicular to the axis of cylindrical specimen. That´s to say that the method is modified to convenient form to use measured waveforms in the x₁-x₂ plane. The measured wave data are fed into the inversion method and cross-sectional images are obtained. We get the numerical results from all directions by finite element method. It is verified that the Kirchhoff inversion works well for shape reconstruction of defects.