Solid Particle Transport in Laminar Flow

Tálita Coffler Botti¹; Márcio da Silveira Carvalho¹

¹ Pontifícia Universidade Católica do Rio de Janeiro

doi:10.20906/CPS/COB-2015-0381

Resumo

The use of directional wells became frequent in the development of oil fields, allowing great progress in exploration. This scenario, however, brings great challenges to operations related to wellbore cleaning, that consists in the removal of cuttings from within the annular through the circulation of drilling fluid. As they are denser than the circulating liquid, the cuttings tend to sediment. Due to the inclination of the well, they may form a stationary bed, which blocks part of the annular, leading to lower flow rate that causes operational problems, such as reduced rate of penetration, higher torque and drag, trapped column and others. This research studies the laminar two-dimensional flow of solid particles suspended in a liquid due to a pressure gradient between two parallel plates, representing a simplified description of the flow that occurs in an annulus during drilling process. The mathematical formulation leads to a coupled system of three differential equations: mass and momentum conservation and particle transport equation, which includes the effects of particle diffusion due to the frequency of interaction between particles, the gradient of viscosity and the density difference between the liquid and the particles. The coupled system is solved by the Galerkin/finite element method. The profile of the particle bed along the channel and the flow rate pressure difference relationship for different flow conditions are determined.

Palavras-chave: Particle transport; viscous resuspension; finite element method; drilling