Currently these vectors are generated at the same time as the wall-distance field
by the same run-time selected algorithm. This will be changed so that the wall-reflection
vectors are only generated and stored if required.
When using models which require the wallDist e.g. kOmegaSST it will
request the method to be used from the wallDist sub-dictionary in
fvSchemes e.g.
wallDist
{
method meshWave;
}
specifies the mesh-wave method as hard-coded in previous OpenFOAM versions.
