Sand Erosion in Multiphase Flow for Slug and Annular Flow Regimes

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 also conducted on two-inch and three-inch elbows in a large scale multiphase flow loop with gas, liquid and sand, for vertical and horizontal multiphase flows, at gas and liquid velocities producing slug and annular flows.  Based on the experiments, the mechanistic model has been improved to predict erosion in several different flow regimes considering the effects of sand particle distribution and particle velocities in multiphase flow.  The results of the experiments are also used to validate the erosion models.