Guided Wave Propagation in Waveguides Surrounded by Rugged and Nonhomogeneous Media

Abstract

By carrying out numerical analyses, this study presents wave propagation characteristics when guided waves propagate in waveguides surrounded by rugged and nonhomogeneous media. The global matrix method is used to facilitate the numerical analyses, and guided ultrasonic wave propagation is assumed to propagate through circular structures (e.g. pipes) embedded in various rugged and nonhomogeneous media such as soils. Specific guided wave modes are selected for better resolution and less wave energy loss by controlling the central wave frequency and acoustic properties such as phase and group velocities in addition to wave attenuation. The results can be useful for nondestructive testing tools for underground pipelines when they transport different types of fluids such as gas and oils and experience an unexpected damage or deterioration. Therefore, a certain damage or deterioration scenarios are considered. Comparing the previous researches in underground pipeline inspection, this study gives more realistic propagation characteristics in comparison to the conventional analyses, which assumed smooth and homogeneous surrounding media.l analyses, and guided ultrasonic wave propagation is assumed to propagate through circular structures (e.g. pipes) embedded in various rugged and nonhomogeneous media such as soils. Specific guided wave modes are selected for better resolution and less wave energy loss by controlling the central wave frequency and acoustic properties such as phase and group velocities in addition to wave attenuation. The results can be useful for nondestructive testing tools for underground pipelines when they transport different types of fluids such as gas and oils and experience an unexpected damage or deterioration. Therefore, a certain damage or deterioration scenarios are considered. Comparing the previous researches in underground pipeline inspection, this study gives more realistic propagation characteristics in comparison to the conventional analyses, which assumed smooth and homogeneous surrounding media.