EXPERIMENTAL STUDY OF THE USE OF PARTICLES FOR TRACKING THE INTERFACES IN PRIMARY CEMENTING OF CONCENTRIC AND ECCENTRIC WELLS

In this study, our recent and new approach for detailed tracking of the interface between well fluid and cement by
using particles is investigated. The particles can enable us to know the precise location of the interface between two
fluids and be sure about displacement efficiency in the annulus. This includes the introduction of intermediate buoyant
particles that reside at the interfaces between successive fluids in a well (e.g., cement-spacer or spacer-mud). Such
particles must overcome strong secondary flows to travel with the interface. For this purpose, the displacement
mechanisms of Newtonian and non-Newtonian fluids in the annulus of vertical and inclined wells is investigated by
using an experimental set-up with concentric and eccentric annular geometries. For more efficient displacement, the
displacing fluid should have a higher density than the displaced fluid, and the intermediate-buoyancy particles that
reside at the interface between successive fluids are introduced into the models. Particle motions are investigated in
models with different fluid rheology and displacement flow rates. This approach for tracking of the interface can
improve the quality of annular cementing of CO₂ wells and thus the storage safety.