As far as I know nu(), as calculated by the viscosityModel, is transferred to the singlePhaseTransportModel.

After defining a singlePhaseTransportModel in your utility, you should be able to access nu():

e.g.

singlePhaseTransportModel testmodel(U, phi);

volScalarField nuTest = testmodel.nu();

https://github.com/OpenFOAM/OpenFOAM-2.4.x/blob/master/src/transportModels/incompressible/viscosityModels/viscosityModel/viscosityModel.H

https://github.com/OpenFOAM/OpenFOAM-2.4.x/blob/master/src/transportModels/incompressible/singlePhaseTransportModel/singlePhaseTransportModel.C

https://github.com/OpenFOAM/OpenFOAM-2.2.x/tree/master/src/transportModels/incompressible/viscosityModels

Thanks dear

Dear Dominik

How to implement fully Developed boundary in outlet in OpenFoam?

How to set SimpleFoam for creeping Flow(Re=0~1)?

Thanks