COMPARISON OF THE IMPACT FORCE ON THE BOTTOMHOLE SURFACE BETWEEN PDC AND ROLLER CONE BITS

Resumo

In the process of drilling the well, the mud is pumped through the drill string, passing through the drill
bit until it reaches the ground, and finally the drilling mud with the particulate material is taken to the surface
through the annulus region. The impact of the fluid that leaves the nozzles of the drill bit to the ground, will allow
the degradation of the soil and removal of the particulate material. The influence of the rotating drill string on the
impact force will be studied through a numerical platform under development based on the Navier-Stokes
equations, discretized using the finite volume method using staggered arrangement, with a second order of
approximation in space and time. The immersed boundary method is employed, where the fluid is represented by
the Eulerian mesh and the geometry by the Lagrangian mesh, which in our case will use two different types of
drill bits (Polycrystalline Diamond Cut-PDC and Roller cone) to compare them. The Large Eddy Simulation
method was also employed with the dynamic sub-grid scale model, which is associated with describing the
turbulence phenomenon. The Reynolds number based on the fluid inlet diameter was 3500.