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===Geometrical Rules & Material Hierarchyin EM.Tempo ===
The following rules apply to the definition EM.Tempo allows overlapping objects although it is generally recommended that object overlaps be avoided in favor of materials clearly defined geometries and object boundaries. If two or more objects of the same material type and group overlap, they are merged using the Boolean union operation during the mesh generation process. If two overlapping objects belong to two different material categories, then the material properties of the FDTD cells in the overlap region will follow the EM.Tempo's material hierarchy rule. In that case, the overlap area cells will always be regarded as having the material type of the higher priority. According to this rule, the material types are ordered from the highest priority to the lowest in the following manner:
* Under the # PEC category, you can define all types of solid, and surface and curve CAD objects.* Under the # PMC category, you can define only define rectangle strip objects parallel to the principal planes. * Under the # Dispersive# General Anisotropic# Uniaxial Anisotropic# Dielectric If planned carefully, Anisotropic and Dispersive taking advantage of EM.Tempo's material categories, you can define only solid CAD hierarchy rule would make the construction of complex objectseasier.* Under the Inhomogeneous Material categoryFor example, you a dielectric coated metallic cylinder can only import a Cartesian "be modeled by two concentric cylinders: an inner PEC of smaller radius and an outer dielectric of larger radius as shown in the illustration below.CAR" data file.* Under The portion of the dielectric cylinder that overlaps the inner PEC cylinder is ignored by the FDTD engine because the PEC cylinder takes precedence over the Thin Wire categorydielectric in the material hierarchy. Alternatively, you can only define line objects parallel to model the principal axessame structure by an inner solid PEC cylinder enclosed by an outer hollow pipe-shaped dielectric cylinder.
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EM.Tempo allows overlapping objects, although it is generally recommended that object overlaps be avoided in favor of clearly defined geometries and object boundaries. If two or more objects of the same material type and group overlap, they are merged using the Boolean union operation during the mesh generation process. If two overlapping objects belong to two different material categories, then the material properties of the FDTD cells in the overlap region will follow the EM.Tempo's material hierarchy rule. In that case, the overlap area cells will always be regarded as having the material type of the higher priority. According to this rule, the material types are ordered from the highest priority to the lowest in the following manner:
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# PEC
# PMC
# Dispersive
# General Anisotropic
# Uniaxial Anisotropic
# Dielectric
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If planned carefully, taking advantage of EM.Tempo's material hierarchy rule would make the construction of complex objects easier. For example, a dielectric coated metallic cylinder can be modeled by two concentric cylinders: an inner PEC of smaller radius and an outer dielectric of larger radius as shown in the illustration below. The portion of the dielectric cylinder that overlaps the inner PEC cylinder is ignored by the FDTD engine because the PEC cylinder takes precedence over the dielectric in the material hierarchy. Alternatively, you can model the same structure by an inner solid PEC cylinder enclosed by an outer hollow pipe-shaped dielectric cylinder.
== EM.Tempo's Computational Domain & Boundary Conditions ==