1. A simulation method executed on a computing device for simulating a three-dimensional structure, such that two-dimensional layered meshing models three-dimensional current flow, comprising the steps of: discretizing the three-dimensional structure into two-dimensional (“2-D”) layers, such that each of the 2-D layers having mesh nodes, such that the mesh nodes for a certain one of the 2-D layers and the respective mesh nodes of one or more other ones of the 2-D layers are non-connectable by perpendicular lines through the 2-D layers, and such that the 2-D layers have varied meshing densities to capture current distribution utilizing adaptive meshing; constructing a two-dimensional basis for each of the 2-D layers; and constructing a one-dimensional finite difference basis between the 2-D layers, such that a synchronization voltage difference between points that span across adjacent layers of the 2-D layers is determined, such that the points are connected, and such that the connected points have different voltage values.