(258d) Using a CFD-DEM Modeling Approach to Predict Drill Bit Dynamics

The increasing demand for energy has resulted in the need to drill for oil and natural gas at greater depths under the earth’s surface. The extreme heat and pressure at such depths produces changes in the operation of traditional drilling components. Correspondingly, more research is being conducted in the optimization of drilling materials and parameters such as the weight-on-bit (WOB), angular velocity and the drilling fluid properties to better perform in such conditions. Along with lab-scale experiments and industrial testing, modeling is a valuable tool to help in this effort. Specifically, modeling can be used to explore the design space in these extreme environments in an economical fashion. In the current work, computational fluid dynamics (CFD) is used to model the drilling fluid while discrete element modeling (DEM) is used to model the porous rock formation.  Physics-based algorithms are employed to couple the model drill bit, the rock formation and the drilling fluid. The model drill bit is rotated and pressed into the rock formation and the rate-of-penetration (ROP) under various conditions is studied.