Erosion in multiphase flows, with entrained sand, is a more complex phenomenon than
erosion in single-phase flow because of the different flow regimes possible. Earlier predictive
models for erosion in multiphase flow were primarily based on empirical data and the accuracy
of those models was limited to the flow conditions of the experiments. A mechanistic model
has been developed for predicting erosion in elbows in multiphase flow considering the effects
of particle velocities in gas and liquid phases upstream of the elbow. Local fluid velocities in
multiphase flow are used to calculate erosion rates in multiphase flow using particle tracking
and erosion equations. Because the mechanistic model is based on the physics of multiphase
flow and the erosion phenomenon, it is expected to be more general than the previous
empirical models. Erosion experiments were conducted on two-inch and three-inch elbows in
a large scale multiphase flow loop with gas, liquid and sand for gas and liquid velocities
producing slug and annular flows. The annular flow experiments were primarily performed in
the upward vertical orientation but a few experiments were performed in the horizontal
orientation. All the slug flow experiments were performed in the horizontal orientation. Based
on the experiments, the mechanistic model has been improved to predict erosion in several
different multiphase flow regimes considering the effects of sand particle distribution and
particle velocities in gas-liquid flows.
Keywords: Sand Erosion, Erosion Modeling, Annular Flow, Slug Flow