MODELING OF BARITE SAG AND FLUID FLOW IN DRILLING FLUIDS

Resumo

The settling of barite, or any other weighting material, causes undesirable fluctuations in the density of drilling fluids. Problems such as stuck pipe, pressure control difficulties and lost circulation are caused by the settling of barite particles. In this work, we studied a biphasic model to describe the settling and transport of barite particles in oil based drilling fluids. The model is based on the conservation equations and uses the Eulerian approach. The model studied was able to predict the settling and the formation of the particles bed, qualitatively the influence of particle size and liquid viscosity and initial solids concentration. We conducted sedimentation experiments to evaluate parameter of the model. The experimental data was analyzed in terms of the one-way ANOVA test for a 95% confidence level and showed significant reproducibility. The simulation results are qualitatively in accordance with the experimental results.