Using forcing from .usr file

[bran0876]

Hi,

I am running the turbChannel tutorial where the momentum forcing is prescribed in the .udf file. I have tried to use the userf and usrdat3 inside the .usr file as given below without success. I believe that the flow is being driven by whatever is being prescribed inside the .udf file and these 2 subroutines are being ignored. How can I make the forcing come from these 2 subroutines (similar to what is done in nek5000) instead of the .udf file?

Thanks

  subroutine userf  (ix,iy,iz,ieg)
  include 'SIZE'
  include 'TOTAL'
  include 'NEKUSE'

  ffx = 0.0
  ffy = 0.0
  ffz = 0.0

  return
  end
  
  subroutine usrdat3
  include 'SIZE'
  include 'TOTAL'

  param(54) = -1  ! use >0 for const flowrate or <0 bulk vel
                  ! flow direction is given by (1=x, 2=y, 3=z)
  param(55) = 1.0 ! flowrate/bulk-velocity

  return
  end

[stgeke]

Please check the par file options (nekrs --help par).

[GENERAL]
constFlowRate               meanVelocity=<float>                       set constant flow velocity
                            meanVolumetricFlow=<float>                 set constant volumetric flow rate
                              + direction=<X,Y,Z>                      flow direction