Hi Kurt, In the high order outflow condition the pressure appears as p n (where n is the normal) and has to be introduced in the relevant velocity component. So if your outflow is normal to the x-direction then the value of p n should appear in the Value of the u-variable. Cheers, Spencer. On 24 Jul 2017, at 22:55, Kurt Sansom <kayarre@gmail.com<mailto:kayarre@gmail.com>> wrote: Hi, I am trying to use the higher order outlet boundary conditions. I know that is formulated for truncated open domains, but am curious if I can use in the following way, where I want to specify the outlet pressure to some value to create back pressure in the system. I realize that for in-compressible flow it doesn't matter that much, but I am interested in implementing a time varying pressure condition at the outlet. I have tried the following boundary condition for a tube and it doesn't appear to apply the VALUE tag? I want to make sure before I file a bug. <REGION REF="2"> <!-- Outlet , N=Neumann=gradient, D=Dierchlet=value R=Robin=mixed--> <N VAR="u" USERDEFINEDTYPE="HOutflow" VALUE="0" /> <N VAR="v" USERDEFINEDTYPE="HOutflow" VALUE="0" /> <N VAR="w" USERDEFINEDTYPE="HOutflow" VALUE="0" /> <D VAR="p" USERDEFINEDTYPE="HOutflow" VALUE="10665" /> </REGION> Regards, ~Kurt -- Kurt Sansom _______________________________________________ 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