Effect of Bentonite Mud Additives on Flow Structure and Cuttings Transport through The Eccentric Annulus of Wellbore

Abstract

The effect of bentonite mud additives on flow structure and cuttings transport efficiency through drill hole (Wellbore) eccentric annular flow is studied numerically and presented in this work. velocity distribution profiles and contours of both drilling fluid and cuttings are examined in The presence of drill pipe rotating. cutting volume fraction distributions as well as flow contours is considered. The effect of additives on The cuttings slip velocity and transportation efficiency is studied. potassium cloride (KCI) and Potassium formate (KF), as wellbore stability, and viscosity control additives are investigated. PG gum as bentonite mud additive for filtration, viscosity, and gel strength control as well as barite additive to control mud density is studied. The study is carried out using fluent 6.3.26 package CFD software. The turbulent model considered is The realizable k-e model. flow passage considered is an eccentric annulus that has inner and outer diameters of 5 cm and 10 cm with 50% eccentricity, and length L =500 cm. base fluid considered is 4.3% bentonite mud. 3%bentonite mud is also investigated with PG gum additives. drilling fluid rheological model considered is The power law. results show that The axial, velocity distributions of both drilling fluids and cuttings, as well as drilled cuttings volumetric fraction distribution are strongly affected by drilling fluid additives. additives modify The flow structure and cuttings distribution, and The effect depends on drilling fluid's rheology as represented by their viscosities. bentonite mud additives reduce cuttings slip and increase cuttings transport efficiency.