Modeling electromagnetics on cylindrical meshes with applications to steel-cased wells
Table 1:Simulation details for the results shown in Figure 4. Note that the discretizations in the Commer FE and FD codes use one element or one cell across the width of the casing, as does the UBC code. The SimPEG simulation uses 4 cells across the width of the casing. For the time-stepping, each chance in step length requires a matrix factorization. Values for the Commer FE and FD solutions are from Commer et al. (2015)Um et al. (2015).
| Mesh | Timestepping | Compute Resources | Compute Time | |
| Commer FE | 8 421 559 tetrahedral elements | 893 time steps 9 factorizations | single core Intel Xeon X5550 (2.67 GHz) | 63 hours |
| Commer FD | 2 182 528 cells | s 120 598 277 time-steps | 512 cores Intel Xeon (2.33 GHz) | 23.2 hours |
| UBC OcTree | 5 011 924 cell | 154 time steps 10 factorizations | single core Intel Xeon X5660 (2.80 GHz) | 57 minutes |
| SimPEG | 314 272 cells | 187 time-steps 7 factorizations | single core Intel Xeon X5660 (2.80GHz) | 14 minutes |
- Commer, M., Hoversten, G. M., & Um, E. S. (2015). Transient-electromagnetic finite-difference time-domain earth modeling over steel infrastructure. Geophysics, 80(2), E147–E162. 10.1190/geo2014-0324.1
- Um, E. S., Commer, M., Newman, G. A., & Hoversten, G. M. (2015). Finite element modelling of transient electromagnetic fields near steel-cased wells. Geophysical Journal International, 202(2), 901–913. 10.1093/gji/ggv193
