nullSelfSplit

nullSelfSplit Parameters

species (string, required)

This specifies the name of the Species block representing the particles to be split.

thresholdFunc (block, required)

This specifies the maximum number of macroparticles existing in a cell for the self-split operation to be applied. The thresholdFunc STFunc can be a space-time dependent function. This threshold is evaluated at each cell and time step. Splitting will not take place in any cell with a greater number of macroparticles than this threshold.

minWeight (real, optional)

This specifies the minimum variable-weight to be given to a particle when self-split variable-weight species. The default value is 1e-5. If the original particle weight is below the minWeight then the split is not performed.

algorithmType (integer, optional)

This specifies the type of algorithm to be used when splitting macroparticles. The possible values are 1 and 2. Algorithm 1 (default) performs a simple, fast split operation, whereas option 2 is more accurate but more computationally intensive. In algorithm 1, the weight of the macro particle is simply split to one half and a new macroparticle gets added at the same location with one half weight value. In algorithm 2, the split operation is done such that the number of macro particles within a cell meets the requirement of the threshold value specified by the user.

splitInterval (integer, optional)

This option specifies the number of time steps interval between two successive split operations. The default value is 1, i.e. the split operation is done at every time step.

<NullInteraction electronSelfSplit>
  kind = nullSelfSplit
  species = electrons
  algorithmType = 1
  splitInterval = 1
  minWeight = 1e-3
  <STFunc thresholdFunc>
    kind = expression
    expression = 100.0
  </STFunc>
</NullInteraction>