Preconditioners for FEM

A number of preconditioners are available when using the finite element method (FEM) (for advanced users only).

Note: It is recommended to use the default settings.
On the Solve/Run tab, in the Solution settings group, click the  Solver settings icon. On the Solver settings dialog, click the Advanced tab.


Figure 1. The Solver settings dialog (Advanced tab).
Multilevel ILU/diagonal decomposition (512)
Preconditioner for a hybrid FEM/MoM solution that uses a multilevel sparse incomplete LU-decomposition with threshold and controlled fill-in.
Multilevel FEM-MLFMM LU/diagonal decomposition (2010)
Preconditioner for a hybrid FEM/MLFMM solution that uses a multilevel sparse LU decomposition of the combined and partitioned, FEM/MLFMM system.

When using the parallel Solver, the factorisation type can be specified.

Multilevel LU/diagonal decomposition (2050)
Preconditioner for a hybrid FEM/MoM solution that uses a multilevel sparse LU decomposition of the partitioned system.

When using the parallel Solver, the factorisation type can be specified.

Note: The number in brackets corresponds to the value of the I3 field at the CG card.