Numerical simulation of the law of response to high-frequency acoustic-induced vibration along gas pipeline with corrosion defects

Abstract

[Objective] High-frequency acoustic energy generated by gas passing through decompression devices induces high-order modes of the pipeline wall, leading to acoustic-induced vibrations of the pipeline structure. These vibrations can potentially trigger fatigue failures at discontinuous, such as welded supports, tees, and areas of pipeline corrosion defects, over a short period. [Methods] Initially, the infuence of sound source strength was quantified by calculating the noise spectrum and converting the sound power levels into sound pressure levels.A finite element model was created to simulate acoustic-induced vibrations in a gas pipeline featuring corrosion defects. Acoustic pressure was applied to the pipeline wall within the model to investigate the impact of corrosion defect dimensions on acoustic-induced vibrations,i.e. length, width, and depth. Subsequently, the obtained results were compared against the evaluation outcomes derived from the Energy Institute(EI) guidelines. [Results] Under varying dimensionless lengths of corrosion defects, the gas pipeline exhibited stress responses characterized by hump-like fuctuations. Specifically, the stress level initially increased and then decreased corresponding to increases in dimensionless defect length. However, the stress concentration weakened with increasing dimensionless defect lengths. As the defect width increased, the gas pipeline showed a uniform stress distribution. Additionally, the pipeline stress fuctuated in a saddle shape with increases in dimensionless defect depth. Specifically, the gas pipeline experienced initial decreases followed by rises in the stress level. [Conclusion] This study reveals the substantial impact of corrosion defects on gas pipeline's stress responses, highlighting the most noticeable impact from the length of corrosion defects. Furthermore, corrosion defects with dimensionless depths over 0.6 lead to significant increases in their infuence on the stress and vibration modes of gas pipelines. Consequently, future research should focus on investigating the impact of corrosion defect depths on acoustic-induced vibrations. The quantitative analysis outcomes of acoustic-induced vibration responses in gas pipelines with corrosion defects not only offer theoretical support for mitigating strong vibrations of gas pipelines but also serve as a reference basis for gas pipelines across design, construction, operation, and maintenance stages.

Keywords

• gas pipeline
• corrosion defect
• acoustic-induced vibration
• fatigue failure
• high-frequency excitation
• energy institute guidelines