Proposed Changes

fix full multigrid

• FMG now has scaled CFL for the coarser meshes during the warmup phase. We also have
  MG_STARTUP_ITER= 50 as config option.
• FMG does an early exit during warmup phase when convergence of 2 orders of magnitude. CONV_FIELD is used as criterion

fix implicit line agglomeration

• for the turbulent flat plate and single core computations, we get an exact agglomeration.
• new config options:
  MG_IMPLICIT_LINES= YES
  MG_IMPLICIT_LINES_MAX_LENGTH= 1000
  MG_IMPLICIT_LINES_ISOTROPIC= YES

For isotropic=yes, every pair of 2x2 nodes is agglomerated, for isotropic=no, we only agglomerate in the direction normal to the implicit line, so the y+ values are preserved.
The implicit line agglomeration works for 2D and 3D, but has been tested more intensively on 2D cases.

Related Work

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