The nutURoughWallFunction is boundary condition that provides a wall function on the turbulent viscosity (i.e. nut) based on velocity (i.e. U) for low- and high-Reynolds number applications for rough walls.


The condition requires entries in both the boundary and field files.

Boundary file

    type            wall;

Field file

    // Mandatory entries
    type                nutURoughWallFunction;
    roughnessHeight     <scalar>;
    roughnessConstant   <scalar>;
    roughnessFactor     <scalar>;

    // Optional entries
    maxIter             <label>;
    tolerance           <scalar>;

    // Inherited entries


Property Description Type Required Default
type Type name: nutURoughWallFunction word yes -
roughnessHeight Roughness height scalar yes -
roughnessConstant Roughness constant scalar yes -
roughnessFactor Scaling factor scalar yes -
maxIter Number of Newton-Raphson iterations label no 10
tolerance Convergence tolerance scalar no 0.0001

The inherited entries are elaborated in:

  • nutWallFunctionFvPatchScalarField.H

  • Suffers from non-exact restart since correctNut() (called through turbulence->validate) returns a slightly different value every time it is called. See nutUSpaldingWallFunctionFvPatchScalarField.C.

Further information


  • N/A

Source code:



  • Introduced in version 2.4.0