Title :
Modeling of EM logging tools in arbitrary 3-D borehole geometries using PML-FDTD
Author :
Hue, Y.-K. ; Teixeira, F.L. ; Martin, L.E.S. ; Bittar, M.
Author_Institution :
Dept. of Electr. & Comput. Eng., Ohio State Univ., Columbus, OH, USA
Abstract :
We discuss the numerical modeling of logging-while-drilling (LWD) tools for hydrocarbon exploration in arbitrary three-dimensional geometries using a new finite-difference time-domain (FDTD) scheme in cylindrical coordinates. Two locally conformal FDTD (LC-FDTD) schemes are employed to simulate eccentric LWD tools in realistic logging environments. An anisotropic perfectly matched layer absorbing boundary condition extended to cylindrical coordinates is incorporated in the FDTD method to simulate unbounded geophysical formations. Frequency-domain data are obtained from the time-domain results using a ramp-modulated sinusoidal source and an efficient early-time extraction algorithm. The FDTD simulations are validated against both numerical mode matching and pseudoanalytical approaches and show very good agreement.
Keywords :
computational electromagnetics; finite difference time-domain analysis; geophysical prospecting; well logging; EM logging tools modeling; FDTD; LWD tools; PML; arbitrary 3-D borehole geometries; cylindrical coordinates; early-time extraction algorithm; finite-difference time-domain; frequency-domain data; hydrocarbon exploration; logging while drilling tools; perfectly matched layer; ramp-modulated sinusoidal source; unbounded geophysical formations; Anisotropic magnetoresistance; Boundary conditions; Data mining; Finite difference methods; Geometry; Hydrocarbons; Numerical models; Perfectly matched layers; Solid modeling; Time domain analysis;
Journal_Title :
Geoscience and Remote Sensing Letters, IEEE
DOI :
10.1109/LGRS.2004.840637
