CFD study of thermal effect on Power-law fluid in rotating annular flow

Drilling in oil and gas industry is a crucial and precarious process. Inaccurate estimation or expectation of any of the parameters interfering in this process can lead to catastrophic results if not handled carefully and in proper timing. One of the main parameters is the drilling fluid, which is used throughout the whole drilling procedure for numerous functions. The drilling fluid is tested under normal atmospheric temperature. However in the drilling process the fluid is exposed to high temperature that can impact the drilling fluid properties and flow behavior. Adding to that the rotation of the drill string impact which can change the dynamic viscosity of the fluid. As more high temperature high pressure wells are being drilled the need to better understand the impact of high temperature in the fluid annular flow became necessary. In this study we tried to understand and investigate the effect of both temperature and rotation on the properties of the drilling fluid and on the flow behavior in a concentric annuli. The scope and methodology of this research involved Computational Fluid Dynamics (CFD) approach, with ANSYS-CFX (in ANSYS 15) as the analysis system, where a CFD model with an optimum mesh size was created and validated against previous experimental data. The fluid was modelled using Power Law rheology.