UBC Theses and Dissertations
Displacement of drilling mud during primary cementing in near vertical oil wells Sood, Shalu
In this thesis, we consider the physical problem that stems from the industrial process of oil well cementing during the well's construction. The laminar flow of non-Newtonian fluids in an eccentric annuli has been the subject of many investigations. The work presented here is part of a combined theoretical-experimental approach to the problem of non-Newtonian displacement. An annular flow loop is constructed so that controlled experiments can be performed on fluid displacements. We conduct a series of experiments using two different carbopol solutions. The drilling muds are non-Newtonian in nature and exhibit a yield stress, we investigate the effects of primary factors, i.e. eccentricity, inclination, density contrast, pH and concentration of carbopol solutions on the displacement of two non- Newtonian fluids in an eccentric annulus. From the experimental results, we classify the regimes of stable and unsteady displacements qualitatively. We report a new phenomenon of flow bypass occurring for concentric cases. We compare our experimental results with a simplified model which allows for a prediction of the displacement flow type. The lubrication model is not in good agreement with the experimental results.
Item Citations and Data