Analysis of multi-particulate flow through the horizontal eccentric annulus considering the borehole cleaning

Abstract

AbstractMulti-particulate flow CFD modelling is carried out while taking eccentricity into account considering drilling horizontal oil wells. The present work focuses on the effect of different cuttings sizes and their concentration on borehole cleaning. The carrier phase is a CMC-Bentonite solution which is a non-Newtonian fluid and the secondary phase is sand cuttings with different sizes. The RNG-k-ε turbulence mixture model is implemented along with the Eulerian-Eulerian multiphase model. The present CFD work has been validated with different experimental work and analytical results. The cutting size distribution in terms of volume fraction has been plotted along the various planes. Contours for volume fraction for different cutting size and inlet cuttings concentrations are also obtained. The increase in turbulence kinetic energy through increase inlet axial slurry velocity and drillpipe rotation (from v = 1 m/s, N = 50 rpm to v = 3.5 m/s, N = 100 rpm) is very effective in reducing cuttings accumulation for slurry A. The migration of cuttings from stationary zone to suspension zone is high for larger cuttings as compared to smaller cuttings from plane P2. The equivalent two-phase simulation for considered five-phase flow of slurry A has the similar cuttings distribution.