Changes

In [[EM.Cube]]'s other modules, material types are specified under the "Physical Structure" section of the Navigation Tree, and sources are organized under a separate "Sources" section. In those modules, the physical structure and its various material types typically represent all the CAD objects you draw in your project. Sources are virtual entities that might be associated with certain physical objects and provide the excitation of your boundary value problem.

In [[EM.Cube]]'s Static Module, materials and sources are all listed under the "Physical Structure" section of the Navigation Tree, and there is no separate "Sources" section. For example, you can define default zero-potential perfect electric conductors (PEC) in your project to model metal objects. You can also define fixed-potential PEC objects with a nonzero voltage, which can effectively act as a voltage source for your boundary value problem. In this case, you will solve the Lapalce equation subject to the specified nonzero potential boundary values. Both types of PEC objects are defined from the same PEC node of the Navigation Tree by assigning different voltage values. Charge and current sources are defined as CAD objects that you must draw in the project workspace.

=== Fixed-Potential PEC Objects===

{{Note| You can define any solid or surface object as a fixed-potential PEC object.}}

=== Dielectric/Magnetic Materials ===

{{Note| You can define any solid object as a dielectric or magnetic material object.}}

=== Volume Charge Sources ===

You can define volume charge sources with a specified charge density in C/m³ confined to certain region of your project. You use [[EM.Cube]]'s [[Solid Objects|solid objects]] to define volume charge sources. All the charge sources belonging to the same group have the same color and same charge density value. The charge density can be positive or negative.

To add a new charge source group to a project, right-click on "Volume Charges" on the Navigation Tree, and select "Insert New Charge Source..." From the Charge Source Dialog, you can change the default purple color of the source group or set the values of the Charge Density.

=== Volume Current Sources ===

To add a new volume current source group to a project, right-click on "Volume Currents" on the Navigation Tree, and select "Insert New Current Source..." From the Volume Current Source Dialog, you can change the default brown color of the source group or set the values of the Current Density magnitude and unit direction vector components. The default direction vector is z-directed.

=== Wire Current Sources ===

{{Note| If you draw [[[Curve Objects]]] under a wire current group, they will be permanently converted to polyline objects before running the simulation engine.}}

=== Permanent Magnets===

In EM.Ferma you don't have to select any specific simulation engine. The program looks at the types sources and material objects present in your project workspace and then it determines whether an electrostatic analysis or a magnetostatic analysis or possibly both should be performed. When there are only electric sources present, you will get nonzero electric fields and zero magnetic fields. When there are only magnetic sources present, you will get nonzero magnetic fields and zero electric fields.

=== Simulation Modes ===

In a "Parametric Sweep", one ore more [[variables]] are varied at the specified steps(s). This means that you must first define one or more [[variables]] in your projects. [[Variables]] can be associated with CAD object properties like dimensions, coordinates, rotation angles, etc. or with material properties or source properties. For each single variable sample or each combination of variable samples, first all the associated CAD object properties, material properties or source properties are updated in the project workspace. Then is a finite difference solution of your updated static structure is computed and parametric sweep proceeds to the next variable sample or combination.

===Static Simulation Engine Settings===

{{Note|The value of convergence error affect the accuracy of your simulation results. For most practical scenarios, the default values are adequate. You can reduce the convergence error for better accuracy at the expense of longer computation time.}}

=== Observables in EM.Ferma ===

[[Image:qstatic.png|thumb|300px|Setting up a Transmission Line simulation.]]

For a step-by-step demonstration (including transmission line [[optimization]]), take a look at this video on our YouTube channel: [http://www.youtube.com/watch?v=Iiu9rQf1QI4 EM.CUBE Microstrip Optimization]