Troubleshooting Electromagnetic Simulations

The Simulation Does Not Finish Properly

The most common cause of crashes is improperly set up particle boundaries. The particle boundaries must completely surround the space in which particles are loaded. Otherwise particles can drift out of the grid and try to reference fields that do not exist. This leads to a Vorpal segmentation fault.

The Output Shows an Unexpected High-Frequency or Checkerboard Pattern

A common problem with electromagnetic simulation is not following the Courant condition [CFL28]. The Courant condition states roughly that the time step must be small enough that a light wave cannot cross more than one cell in a single time step.

High-Frequency and checkerboard patterns can be symptoms of an instability resulting from violating the Courant condition.