Temperature and pressure effects of drilling fluid on cutting transport using CFD simulations

Simulation of liquid-solid flow in annulus of oil wells is of a great importance to predict the two-phase flow field in wellbore accurately. In this paper, direct effects of drilling fluid rheological properties by Herschel-Bulkley model on cuttings transportation, pressure drop, and other parameters of two-phase flow are numerically investigated at different temperatures and pressures. Recent studies have not addressed these effects. Thus, a 3D form of a steady-state and isothermal model is used to simulate the two-phase flow in various temperatures and pressures of drilling fluid, flow rates, and drilling pipe rotations. The governing equations created a system of coupled partial differential equations solved using the iterative finite volume method. The comparisons between the results of the model and experimental data and also analytical relation showed that the model can accurately predict two-phase flow in the annulus. The results indicated that the elevation of temperature and reduction of pressure contributes to a decrease in the cuttings transportation. For drilling fluid velocity of 0.75m/s, the cuttings transportation has been decreased 2.08% by increasing temperature from 70 degrees C to 90 degrees C in 0.1MPa, whereas in pressure of 10MPa, about 1.63% reduction on the transportation of cuttings yielded. (c) 2017 Curtin University and John Wiley & Sons, Ltd.