A Parallel, Fourier Finite-Element Formulation with an Iterative Solver for the Simulation of 3D LWD Measurements Acquired inDeviated Wells

摘要

We describe a new method to simulate resistivity measurements acquired with induction logging instruments in deviated wells. The method combines: (1) a highly efficient iterative solver, (2) a parallel implementation, (3) a Fourier Finite-Element (FFE) formulation in a non-orthogonal system of coordinates, and (4) a 2D hp-Finite Element (FE) goal-oriented self-adaptive grid-refinement strategy. We apply the new method to simulate measurements acquired with a logging-while-drilling (LWD) instrument operating at 1.75 MHz in a 55-degree deviated well. Numerical results confirm the high-accuracy and efficiency of the method. An error level below 1% is achieved in reservoirs with high-contrast in electrical resistivity using an average CPU time of 1-3 minutes per logging position.