A Comparative Study of Laminar-Turbulent Displacement in an Eccentric Annulus under Imposed Flow Rate and Imposed Pressure Drop Conditions

This paper presents a series of experiments focused on the displacement viscoplastic fluids by various Newtonian and non-Newtonian from long horizontal, eccentric annulus. The flow regimes range high Reynolds number laminar through to fully turbulent. These represent primary cementing operation in horizontal well. main objective our is gain insight into role regime fluid-fluid flows relevance cementing. We study strongly annuli displaced with significant yield stress, i.e., those scenarios where mud channel most likely persist. For annuli, displacements are uniformly poor, regardless regime. improves for an eccentricity 0.7. However, at these large eccentricities that typical well cementing, generally poor involves rapid “breakthrough” advance along wide upper side annulus followed only much slower removal residual fluids. dynamic renders contact time estimates meaningless. conclude some simple statements/preferences widely employed industry do not necessarily apply all design scenarios. Instead, detailed involved specification operational constraints needed improved quality.