Extending Operating Life - Flow Induced Vibration

Challenge

Flow Induced Vibration (FIV), and the related problems of pulsation and Acoustic Induced Vibration (AIV), are induced by flow and pressure fluctuations in piping systems and can lead to accelerated fatigue failure if not properly identified and mitigated. In this case, our client was anticipating dead-leg pulsation, due to high multiphase flow past a dead-leg entrance, and needed to understand its magnitude, fatigue life implications, and whether it could be mitigated.

We have invested heavily in developing and validating methods for FIV and AIV characterisation, and deployed them here. Computational Fluid Dynamics (CFD) was used to develop loading spectra then applied to frequency domain Finite Element Analysis (FEA) to establish stress spectra. Using frequency domain cycle counting methods we were then able to calculate fatigue lives for critical elements.

Our work

Outcome

In this case we were able to confirm that despite initial assessments, pulsation was not going to cause accelerated fatigue failure, saving our customer the considerable expense of re-designing the component.

Hydrodynamics – power and performance

Integrity assurance for additively manufactured parts

Built Environment – comfort and safety

Buckling pin failure – The success of simulating plant data

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Case Study

Extending Operating Life – Flow Induced Vibration