An algorithm for aligning a quadrilateral grid with internal boundaries (Q1587868)

A new numerical algorithm that aligns a quadrilateral grid with internal alignment curves (IACs) is presented. The authors describe a more difficult IAC algorithm needed to align the grid with the embedded quadrilaterals. They also combine the two algorithms to illustrate the robustness of the approach over a wide range of examples with internal discontinuities. An electromagnetic calculation is also included, where the IAC algorithm is used to align the grid with a discontinuity in the dielectric constant.