MomentumTransportModels::k-omega model: Improved omega bounding using nutMaxCoeff

Omega lower limit bounding is now based on a maximum turbulence viscosity nut
rather than a minimum omega value which improves stability and robustness of
the k-omega models in case of numerical boundedness problems.

The maximum nut value is calculated by multiplying the laminar viscosity by
nutMaxCoeff which defaults to 1e5 but can be set by the user in the
momentumTransport dictionary.

applications/utilities/preProcessing/applyBoundaryLayer/applyBoundaryLayer.C

@@ -195,7 +195,6 @@ int main(int argc, char *argv[])
                 refCast<const incompressible::RASModel>(turbulence());
 
             omega = (1 - mask)*omega + mask*ce0*sqrt(k)/(Cmu*min(y, ybl));
-            bound(omega, rasModel.omegaMin());
 
             // Do not correct BC - G set by the wall-functions is not available
             // omega.correctBoundaryConditions();