A Strategy for modelling rotating annular flow within CFD is developed with the aid of the wall y
. The strategy will allow the pressure loss, and the effect any drilling tools has on this, to be investigated and analyzed at a reduced time and cost compared to more conventional methods. Five turbulence models were investigated and the k – ω model was found to be the most accurate for a wall y
of less than 5 due to the low Reynolds number found in these flow situations. The k – ε model performed least well, upon investigation of the turbulence models it was found that there was a direct link between the turbulent intensity found in the annulus and the performance in predicting pressure loss. The k – ε model was found to drastically over predict the turbulent kinetic energy for the mesh set up and thus gave inaccurate results regarding the pressure loss in the annulus. This paper suggests that a structured mesh with a y
< 5 and the k – ω turbulence model will provide sufficiently accurate data in the investigation of pressure loss in an annulus.