Pipeline Elbow Corrosion Simulation for Strain Monitoring with Fiber Bragg Gratings

Area of Science:

• Materials Science
• Mechanical Engineering
• Structural Health Monitoring

Background:

• Traditional non-destructive testing methods lack real-time corrosion monitoring capabilities for pipe elbows.
• A robust mathematical model for correlating strain with elbow corrosion is needed.

Purpose of the Study:

• To develop and validate a finite element model for analyzing strain changes in corroded pipe elbows.
• To establish a reliable method for real-time corrosion monitoring using fiber Bragg grating (FBG) strain sensors.

Main Methods:

• Finite element modeling was employed to simulate strain variations in pipe elbows under hydrostatic pressure and bending loads.
• Distinguishing between hoop and axial strains was used to isolate corrosion effects from temperature variations.
• Corrosion degree was quantified by analyzing the difference between hoop and axial strains.

Main Results:

• Under hydrostatic pressure, strain differences showed minimal correlation with increasing corrosion.
• Under bending moment loading, strain differences increased proportionally with the degree of corrosion.
• Strain induced solely by bending moment loading effectively characterizes the corrosion degree.

Conclusions:

• Bending moment-induced strain is a reliable indicator of pipe elbow corrosion.
• Optimal placement for FBG sensors is at the extrados of the pipe elbow for maximum strain sensitivity.
• The findings support the development of FBG-based systems for real-time corrosion tracking and predictive maintenance of pipelines.