CFD modeling encompassed the simulation of flow in the annulus, and a comprehensive effort has been made to understand the flow dynamics using the numerical results.
CFD simulation included study of flow in two cross-sectional planes - (a) axial cross-section and (b) horizontal cross-section. The different geometrical shape was also considered in the analysis.
Flow features including pressure drop and velocity distribution corresponding to wellbore shape and fluid rheology were investigated.
The geomechanical aspects of elliptical shape wellbore are investigated using a commercial package, ANSYS.
The drilling operation is posed with new challenges every day as we are exhausting our conventional and easy target zones. With increasing demand and complexity, there is a need for a continuous update in the system to investigate the flow features and well integrity more accurately. In this paper, the pressure loss was compared for the regular profile of wellbore to the real profile of the wellbore to understand the fluid dynamics in the wellbore. In addition, the wellbores are usually not perfectly sized as the drill-bit size. The wellbore can be enlarged due to breakout, washout, and erosion. These phenomena can consequently affect the drilling fluid dynamics in annulus such as the efficiency of cutting transport, cementing, cutting depth analysis in mud logging and equivalent circulating density. The objective of this research is to evaluate the effect of wellbore geometry on pressure loss, velocity profile, and geomechanical stresses. Wellbore geometry obtained by caliper logs are used, and computational fluid dynamics studies were conducted on the digitized log data. In addition, geomechanical models were constructed with the different non-circular shape of the wellbore to study its effect on hoop stresses in the nearby region.
