Acoustic Forward Model for Guided Wave Propagation and Scattering in a Pipe Bend

Area of Science:

• Non-destructive testing
• Acoustic wave propagation
• Material science

Background:

• Pipe bends are prone to wall thinning from fluid flow corrosion.
• Traditional ultrasonic testing is slow and expensive for bend inspection.
• Guided wave tomography offers whole-area monitoring but requires effective forward models.

Purpose of the Study:

• To develop a simplified yet accurate forward model for guided wave tomography of pipe bends.
• To address the challenge of modeling wave propagation in complex bend geometries.
• To enable efficient and cost-effective monitoring of pipe bend integrity.

Main Methods:

• Developed a 2D acoustic forward model by transforming the 3D bend into an anisotropic rectangular domain.
• Utilized Thomsen parameters to account for directional wave velocity variations.
• Validated the model against experimental data on a 220 mm diameter pipe bend.

Main Results:

• The 2D model effectively simulated wave propagation in the pipe bend.
• The model accurately predicted wave-field focusing and steering effects.
• Experimental results showed good agreement with model predictions, including scattered wave-fields from defects.

Conclusions:

• The proposed 2D anisotropic acoustic forward model is a viable and efficient tool for guided wave tomography of pipe bends.
• This method can improve the accuracy and reduce the cost of inspecting pipe bends for wall thinning.
• The model's ability to capture wave phenomena enhances defect detection capabilities.