Erosion Prediction in Pipeline Elbow by Coupling Discrete Element Modeling (DEM) with Computational Fluid Dynamics (CFD)
AUTHOR(S)
A. Dubey, D. Vedapuri, R. J. B. Smith
PUBLISHER
NACE International
SOURCE
CORROSION 2014
YEAR
ABSTRACT
Erosion in oil and gas pipelines occurs when sand particles impact pipeline walls either due to a change in flow direction or any restrictions in the line of flow. Monitoring is difficult in uninhabited terrain like deep sea, deserts and mountains through which pipelines often pass. Hence it is important to reliably predict the erosion rates which will allow for design precautions to avoid problems. The current solid particle erosion prediction models are either empirical or semi empirical in nature and the suitability over wide ranges of operations is questionable. Erosion models have been implemented in a computational fluid dynamics (CFD) framework. The treatment of particle shapes and the particle–wall, particle–particle and particle–flow interactions are simplified in a CFD framework. An improvement in the modeling of these interactions could help reduce the errors in prediction. In a coupled CFD– Discrete Element Method (DEM) framework, the fluid is modeled using the CFD approach, the solid particles are modeled using DEM in the Lagrangian frame and the interactions are also modeled. The DEM framework accounts for particle shapes and the particle rebound from the wall upon impact. Since erosion is a direct result of energy lost by the particle via impact (normal and tangential), the cumulative energy loss of particles can be quantified and the erosion on the pipe wall can be predicted. In this work, the CFD–DEM approach is used to model erosion in a pipe elbow and the results are compared with the experimental results and predictions using the single particle erosion models in the CFD framework.
KEYWORDS
CFD, dem, erosion, Mechanistic model