Multifield-malUpdater

malUpdater

Works with VSimEM, VSimPA, and VSimMD licenses.

The malUpdater is a MultiField updater that uses isotropic electric and magnetic damping profiles to absorb an incident wave in a slab. These Matched Absoring Layers (MALs) are more stable than Perfectly Matched Layers (PMLs), which use the same electric and magnetic damping profiles, but are anisotropic.

malUpdater Parameters

The malUpdater takes the lowerBounds and upperBounds parameters of FieldUpdater, as well as the following parameters:

upperOrLower (required string): A string specifying whether the damping increases (upper) or decreases (lower) as the coordinate increases.

numOrDenom (required string): A string, specifying whether this updater damps field by (1 - xi^pwr) (num) or 1/(1 + xi^pwr) (denom)

writeField (required string): A string indicating field to damp. (E) or (B).

dir (required integer): An integer, 0-ndim, in which damping coefficient should vary. (0), (1), or (2).

frac (optional float): The peak damping amplitude: 0.5 is suggested, typical range is 0.125 to 2.0.

power (optional float): The damping profile goes as frac*x^power: 3.0 is suggested, typical range is 1.0 to 4.0.

Example malUpdater Block

<FieldUpdater malexlow>
  kind = malUpdater
  lowerBounds = [0  0  0]
  upperBounds = [MAL_THICKNESS  NY  NZ]
  upperOrLower = lower
  numOrDenom = denom
  writeField = E
  dir = 0
  frac = 0.5
  power = 3.0
</FieldUpdater>