CST2013: TLM Solver Parameters

Simulation: Solver Start Simulation (Hexahedral TLM mesh type)

Solver settings frame

Mesh Type

This settings decides which solver to use. The transient solver is used when Hexahedral is selected, and the TLM solver is used when Hexahedral TLM is selected.

Accuracy

This setting defines the steady-state monitor. It influences the duration of the simulation. It is a value for the accuracy of the frequency domain signals that are calculated by Fourier Transformation of the time signals.

This setting must be understood only in connection with the processing of the time signals. Errors made by discretizing a structure can only be influenced by manipulating the mesh.

Every simulation stops at some time. This means that the signals that are calculated are truncated at this point, regardless of their values. If these values are non-zero, the Fourier Transformation will produce an error because only a part of the ”whole” signal with all of its non-zero values has been used for the transformation. Therefore, the ”smaller” the signals are, the more accurate the frequency domain values will be.

To get a value for the accuracy, the amplitudes of the time signals as well as the total energy inside the calculation domain are used. During the simulation, the total energy value is frequently calculated and related to the maximum energy that has been monitored thus far. You can find the corresponding energy curve in logarithmic scale in the 1D Results folder and the simulation stops when the defined accuracy level is reached. However, in some cases, the calculation may last a little bit longer due to the mentioned accuracy check of the time signals.

Store result data in cache

Check here if you want the solver results to be stored in the result data cache. The efficient usage of the result data cache is explained in the printed documentation "Advanced Topics".

Stimulation settings frame

Source type

Define here the type of excitation, choosing between ports and plane wave excitation.

S-parameter settings frame

Normalize to fixed impedance: S-Parameters are always normed to a reference impedance. You may either select to norm them to the calculated impedance of the stimulation port or you may specify a number of your choice.

S-parameter symmetries: Selecting this check button activates the S-parameter symmetry settings made in the S-parameter list... dialog box. These settings should be made due to occurring structure symmetries to save simulation time. The solver only starts the necessary calculation runs; the remaining results will be copied, including time signals. The symmetry conditions are only applied to the selected port mode stimulations.

Start

Calculates the port modes and starts the time domain calculation.

Optimize...

This button opens a dialog box that allows you to set up and start an optimization run.

Par. sweep...

Opens the parameter sweep dialog.

Acceleration...

Opens the acceleration dialog box to control the high performance options of the simulation run (e.g. GPU acceleration, Distributed Computing, MPI).

Specials...

This button leads to a dialog where further special settings for the solver can be made. The settings are for expert users only and should generally not be changed.

Apply

Stores the current settings. The dialog box remains open.

Close

Closes this dialog box without performing any further action.

Help

Shows this help text.