Hi Neks, I am trying to extrude 2D fields .fld to 3D fields. To do so I followed what was said there http://lists.mcs.anl.gov/pipermail/nek5000-users/2013-October/002333.html . It worked fine for the velocities and the temperature fields, but for the pressure, I am having some troubles. I am using the PN/PN-2 approach, and so my velocities and pressure are not defined on the same grid, but the pressure values that I can recover from the .fld are mapped on the velocity grid. My question then would be: is there a (quick) way to have the pressure "projected back" on its grid ? Did anyone has this problem ? Thank you for your help, Pierre-Emmanuel des Boscs.