Numerical modeling of tool-rock interaction in laminated formations

Abstract

Based on a review of the literature, a numerical model of the chip formation process in laminated rock formations has been developed. The model uses a finite element approach to simulate the anisotropic behavior of laminated rock formations.

The finite element program has been developed with the assumption of two-dimensional plane strain. Anisotropic elements and dynamic loading are used to represent the actual penetration process of a bit tooth. An iteration method, using an incremental approach, has been applied for the continuous tooth penetration process. Displacements and axial loads have been modified after each iteration.

The program provides quantitative information on stresses and displacements during the penetration process. Furthermore, bit deviations in laminated formations can be inferred.. Different rock strength characteristics have been employed on each side of the bit Bit tooth-rock interaction for various formation dips (from ()O to 9(0) of the Berea sandstone have been simulated and compared with experimental results.