MeshAdaption3D Object

This object allows you to change the parameters used for the three dimensional adaptive mesh refinement. This procedure is an automatic scheme which uses the results of a performed calculation to estimate a mesh better suited for the given problem. With the refined mesh a new calculation pass will then be started. The whole procedure will be repeated until a convergence is met.

• Methods

• Default Settings

• Example

Methods

 AccuracyFactor ( double value )

Specifies an additional factor for the current accuracy setting made in the transient solver control dialog box. The change of the S-parameters between two subsequent passes must not differ by more than the given accuracy level multiplied with the defined accuracy factor.

SetType ( enum type )

Sets the type.

key may have one of  the following values:

SetAdaptionStrategy ( enum key )

Specifies the type of mesh adaption strategy.

key may have one of  the following values:

ErrorEstimatorType ( enum type )

Specifies the error estimator.

type may have one of  the following values:

RefinementType ( enum type )

Specifies the refinement type.

type may have one of  the following values:

MinPasses ( int passes )

Specifies the minimum number of passes which will be performed for the adaptive mesh refinement, even if the results do not change significantly.

MaxPasses ( int passes )

Specifies the maximum number of passes to be performed for the adaptive mesh refinement, even if the results have not sufficiently converged so far. This setting is useful to limit the total calculation time to reasonable amounts.

CellIncreaseFactor ( double factor )

Determines how many new cells are introduced between two subsequent passes of the mesh refinement. A setting of 0.5 means that the number of mesh cells increases about 50 percent from pass to pass.

WeightE ( double weight )

Specifies the weight of the electric energy compared to the part of the magnetic energy. Sometimes a structure’s behavior is more critically coupled to changes of the electric field than to changes of the magnetic field so that it is advisable for the refinement control to take this fact into account.

WeightB ( double weight )

Specifies the weight of the magnetic energy compared to the part of the electric energy. Sometimes a structure’s behavior is more critically coupled to changes of the magnetic field than to changes of the electric field so that it is advisable for the refinement control to take this fact into account.

RefineX ( bool switch )

Decides whether the adaptive mesh refinement will be performed in the x-direction (switch = True) or not (switch= False). This option is useful to avoid refining a mesh along coordinate directions in which the structure’s fields have no dependency.

RefineY ( bool switch )

Decides whether the adaptive mesh refinement will be performed in the y-direction (switch = True) or not (switch= False). This option is useful to avoid refining a mesh along coordinate directions in which the structure’s fields have no dependency.

RefineZ ( bool switch )

Decides whether the adaptive mesh refinement will be performed in the z-direction (switch = True) or not (switch= False). This option is useful to avoid refining a mesh along coordinate directions in which the structure’s fields have no dependency.

MaxDeltaS ( double value )

The S-parameter error (Delta S) is determined as the maximal deviation of the absolute value of the complex difference of the S-parameters between two subsequent passes. Specify a value between 0.0 and 1.0.

MeshIncrement ( int value )

Only for Expert system based strategy. Specifies the number of mesh lines to add to the Mesh.MinimumLineNumber setting after a pass has been completed.

SetFrequencyRange ( bool auto, double min, double max )

Limits the frequency range used for the adaptive mesh refinement.

SkipPulses ( double value )

Specifies the number of pulse widths to be skipped in order to consider very narrow banded structures, where the greatest energy amount is reflected and thus would mislead the refinement procedure. This means that it is advisable to start the energy calculation not until the reflected energy parts have left the structure.

NumberOfDeltaSChecks ( int value )

Defines the number of consecutive adaptive tetrahedral mesh refinement passes during which the S-parameter deviation has to meet the threshold value defined by MaxDeltaS before the results are accepted to be converged.

NumberOfPropConstChecks ( int value )

Defines the number of consecutive adaptive tetrahedral port mesh refinement passes during which the propagation constants have to meet the threshold value defined by PropagationConstantAccuracy before the results are accepted to be converged.

PropagationConstantAccuracy ( double value )

Defines the desired accuracy of the propagation constants for the adaptive tetrahedral port mesh refinement in terms of kz/k0, where kz is the mode's propagation constant, and k0 is the freespace propagation constant of a plane wave.

ImproveBadElementQuality ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. The solver will try to reduce the number of bad elements if the flag is set to True.

SubsequentChecksOnlyOnce ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh, and multiple adaptation frequency samples. Usually, the S-parameter convergence of the adaptive mesh refinement is checked more than once (see NumberOfDeltaSChecks). The solver will apply this check only to the first mesh adaptation sample if the flag is set to True.

WavelengthBasedRefinement ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. Each edge of an element will be refined if its length is greater than the desired fraction of a media wavelength at the adaptation frequency, as defined in the mesh properties. In most cases, the initial mesh fulfills this criterion already. If the material properties are not known in advance, as is the case for inhomogeneously biased ferrites, then this option should be enabled.

MinimumAcceptedCellGrowth ( double value )

This setting only applies to the frequency domain solver with tetrahedral mesh. It enforces an additional convergence criterion, which rejects a "small" delta S (below the desired threshold) if the number of mesh cells did grow less than value percent.

ManualThetaRef ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. It enables or disables manual setting of a refinement percentage, which can be specified by the command  RefThetaFactor (  double value  ).

RefThetaFactor (  double value  )

Defines the refinement percentage.  The error estimator assigns a measure for the error to each edge. Edges with the highest error measures are selected for refinement until their contribution to the overall estimated error is a certain value, called refinement percentage. It is 30% per default. In addition, this setting is an approximated upper limit for the mesh cell increase.

SnapToGeometry ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. When selected, new nodes that are generated on model interfaces during the mesh adaptation will be projected onto the original geometry, such that the approximation of curved surfaces is improved after each adaptation step.

EnableInnerSParameterAdaptation ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. It enables the S-parameter convergence criterion for the adaptive mesh refinement at discrete mesh adaptation samples.

EnablePortPropagationConstantAdaptation ( bool flag )

This setting only applies to the frequency domain solver with tetrahedral mesh. It enables the propagation constant convergence criterion for the adaptive port mesh refinement for waveguide ports.

Default Settings

MinPasses (2)

MinPasses (6)

CellIncreaseFactor (0.7)

WeightE (1.0)

WeightB (1.0)

RefineX (True)

RefineY (True)

RefineZ (True)

MaxDeltaS (0.02)

MeshIncrement (5)

SetFrequencyRange (True, 0.0, 0.0)

SkipPulses (0.0)

NumberOfDeltaSChecks (2)

NumberOfPropConstChecks (2)

PropagationConstantAccuracy (0.005)

ErrorEstimatorType("Automatic")

RefinementType("Automatic")

ImproveBadElementQuality (True)

SubsequentChecksOnlyOnce (False)

WavelengthBasedRefinement (True)

ManualThetaRef (False)

RefThetaFactor (0.3)

MinimumAcceptedCellGrowth (0.5)

SnapToGeometry (True)

EnableInnerSParameterAdaptation (True)

EnablePortPropagationConstantAdaptation (True)

Example

With MeshAdaption3D

    .SetType ("Time")

    .SetAdaptionStrategy ("ExpertSystem")

    .MinPasses (2)

    .MaxPasses (6)

    .MeshIncrement (5)

    .MaxDeltaS (0.02)

    .SetFrequencyRange (True, 0.0, 0.0)

End With