Hi Fabian, There is a filter for some of this stuff for the incompressible formulation. The filter for this is under the solver so have a look at $Netar/solvers/IncNavierStokesSolver/Filters/FilterReynoldStresses.cpp For the divergence there is a gradient module in FieldConvert. We should probably also introduce a Divergence module. The main challenge here is the manipulation of the variable names to remove the rho from the compressible variables. I think I am suppose to be sorting out a branch for this which I will try and look at soon! Cheers, Spencer. On 17 Nov 2016, at 18:07, Selbach, Fabian <fabian.selbach@student.uni-siegen.de<mailto:fabian.selbach@student.uni-siegen.de>> wrote: Dear users, I have two problems/questions: First I would like to compute the time averaged field of the 'turbulent kinetic energy' and 'dissipation' at the end of my compressible flow solver simulation. How can I generate them? Is there already any filter? In the user-guide I realized the option "to compute time-averaged fields for each variable defined in the session file" at page 40. By default my variables in the compressible flow solver are: rho, rho*u, rho*v, rho*w and E. So it's only possibly to generate the time-averaged values of them or do I have any other option? And my second question: How can I compute the divergence u at an instantaneous time step? Best regards Fabian _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users Spencer Sherwin McLaren Racing/Royal Academy of Engineering Research Chair, Professor of Computational Fluid Mechanics, Department of Aeronautics, Imperial College London South Kensington Campus London SW7 2AZ s.sherwin@imperial.ac.uk<mailto:s.sherwin@imperial.ac.uk> +44 (0) 20 759 45052