ENH: linear solvers: add variable-specific debug flags

See merge request !478

Kutalmış Berçin authored 3 years ago and Andrew Heather committed 3 years ago

Introduces a new optional keyword of label type 'log'
to linear-solver dictionaries to enable variable-specific
debug statements. For example, in fvOptions file:

    solvers
    {
        p
        {
            solver GAMG;
            ...
            log    2;
        }

        U
        {
            ...
            log    0;
        }
    }

The meanings of values of 'log' are:

    log    0;    <!--  no output
    log    1;    <!--  standard output
    log    2;    <!--  debug output
    // values higher than 2 are expected to have no effect

This keyword does not directly affect the operations of various
DebugSwitches and backward compatibility has been ensured in exchange
of code cleanness. The related DebugSwitches are:

    DebugSwitches
    {
        SolverPerformance    0;
        GAMG                 0;
        PCG                  0;
        PBiCG                0;
        smoothSolver         0;
    }

Implicit treatment of coupled boundary conditions

See merge request !477

- liquid film, blockMesh changes, multiWorld communicators

- previously reported the WM_PROJECT_VERSION in the top banner
  but this makes it overly sensitive to arbitrary user naming.

  Change to the current API in the comment banner, include the
  WM_PROJECT_VERSION as part of the reported "Build: ..."
  string instead.

improve handling of multiple world communication

See merge request !480

- cleanup initialization (to avoid stealing tokens)

- previously had a patch-size check, which caused a zero-sized patch
  to be "sticky" as uniform Zero regardless of what the original input
  stated (eg, "constant 0.5")

  This was caused by short-circuiting logic that circumvented reading
  on zero-size patches.

- dictionary parameters to change the bend angle

- blockMesh transform parameters to allow different orientations

- support non-uniform scaling, prescaling and cartesian coordinate
  transformations.

  Eg, stretch in one direction and then rotate
  ```
  prescale  (1.5 1 1);
  transform
  {
      origin   (0 0 0);
      rotation
      {
          type  axisAngle;
          axis  (0 0 1);
          angle 45;
      }
  }
  ```

- support "transformed" versions of blockMesh vertices, topology.
  With the additional of transformations etc, a simplistic application
  of a single scale parameter is no longer sufficient.

    new:  blMesh.vertices(true);
    old:  blMesh.vertices() * blMesh.scaleFactor();

    new:  blMesh.topology(true);
    old:  N/A

- add individual edge access for blockDescriptor.
  Saves copying and duplicate calculations.

- handle '(block face)' specification for curved faces,
  which is ok for external block faces, but likely somewhat
  questionable if used for internal block faces.

- searchable box, boxToCell, boxToFace, boxToPoint

- added hexCell for some more encapsulation

- Can specify
  ```
  transform
  {
      origin      (1 2 3);
      rotation    none;
  }
  ```
  instead of the longer form
  ```
  transform
  {
      origin      (1 2 3);
      e1          (1 0 0);
      e3          (0 0 1);
  }
  ```

COMPAT: remove old (pre-1812) Euler and STARCD keywords

- use "angles", remove old compat name "rotation"
  as clutter and possible confusion with "coordinate rotation"

STYLE: remove coordinate rotation move constructors

- an unnecessary holdover from older code.

- separate handling of auxiliary files vs time directories

- restore0Dir: avoid removing 0/ if 0.orig/ does not exist

finiteArea: new models and solvers for films

See merge request !475