Flow of cement slurry through an eccentric annulus

Abstract

A step by step procedure has been developed to design cement hydraulic during cement job
to minimize non cemented channels or bad cement job by taking into consideration the
non-flow area throughout the eccentric annulus. Since cement slurry exhibit non-
Newtonian rheological behavior, a good description of the slurry rheology is required in
order to estimate accurately the velocity profile across the annulus. To achieve this goal,
six rheological models have been adopted: Power-law, Robertson-Stiff, Bingham, Casson,
Modified Power-law, and Modified Robertson-Stiff Models. Using the last five rheological
models, new frictional pressure gradient equations for laminar flow of cement slurry
through an eccentric annulus have been derived by the author based on slit-approach
approximation.