One of the primary functions of the drilling fluid is to transport cuttings from the bit to the surface. Thistransport is mainly a function of fluid properties (rheology and density), pump rate, wellbore trajectory andgeometry, drillstring rotation and eccentricity. Because these interrelated parameters all have a significanteffect on cuttings transport, it is important that hole cleaning modeling is comprehensive and inclusive toyield useful, reliable results. Inaccurate models that either do not consider significant effects or oversimplifythem can lead to inadequate hole cleaning advice, resulting in non-productive and invisible lost time. A novel cuttings transport model that includes relevant effects such as pipe rotation, eccentricity and theannular blockage is presented. Local velocity profiles are calculated for a given fluid and compared againstthe local critical velocity for cuttings transport. Then, the location and the magnitude of annulus blockage arenumerically assessed. After an annulus becomes partially blocked with cuttings deposited in a cuttings bed,continuity and momentum equations are solved for the blocked annulus to estimate the new local velocities.The annulus is divided into small sections and the pressure profile is calculated with the progression of time.By doing so, a realistic representation of a wellbore's pressure and velocity profiles is obtained.
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