Flow-Induced Vibration in Piping Systems

Abstract

Flow-Induced Vibration (FIV) is a commonly observed phenomenon encountered in many engineering applications, particularly in the context of pipeline systems. The interaction between fluid flow and structural elements such as pipes can cause vibrations, which may contribute to fatigue failure with time. Accurate prediction methods for natural frequency and critical velocity are essential due to the significant impact they have on pipeline reliability. This project's primary aims were to evaluate Finite Element Analysis (FEA) models' ability to estimate the natural frequency and critical velocity of a simply supported pipes conveying fluid without considering the Coriolis force term in the equation of motion. the second aim was to use Finite Difference Analysis (FDA) for similar predictions and compare it to FEA models. The project focused on simply supported pipes, ensuring free vibration, and considered different pipe materials. Two numerical approaches were used: Finite Element Analysis (FEA) and Finite Difference Analysis (FDA). For the FE model, an equation of motion eliminating the Coriolis force term was used to assess the impact of this term on predictive accuracy. The results showed that eliminating the Coriolis force term increased critical velocity predictions. In particular, the FE model including the Coriolis force term from previous studies predicted critical velocity better. Both FE-models, including Coriolis force term or not , predicted the natural frequency identically. FDA determined pipe stability, natural frequency, and critical velocity in the second aim. FDA predicted critical velocity better than FEA, especially for stiffer materials. FDA and FEA models predicted natural frequency similarly for all materials. This project compares FEA and FDA accuracy to understand Flow-Induced Vibration in pipeline systems. It investigates the effects of removing the Coriolis force from term equations of motion. More complex boundary conditions may improve these findings in future studies.