NS periodic boundary conditions

[isabelmonteiro]

I'm running a ROMS application with NS_PERIODIC boundary conditions:
# define NS_PERIODIC
#define EASTERN_WALL
# define WEST_FSCHAPMAN
# ifdef SOLVE3D
# define WEST_M3RADIATION
# define WEST_TGRADIENT
# define WEST_KGRADIENT
#endif
I've adjusted my bathymetry file to have h, pm and pn equal at the N and S boundaries. It is a small domain so I also set f=constant.
What I get is very puzzling : u,v and of course T,S and zeta are different at the N and S boundaries except for time-step one. I mean what gets out of the domain at the S boundary is different that what enters in the domain at N boundary.
Am I forgetting something when prescribing NS_PERIODIC?

[kate]

There could be a bug in the NS_PERIODIC since it doesn't get used very often. This seems to call for some debugging... Not having your setup, one could try creating an UPWELLING problem that's rotated 90 degrees to see if it's periodic.

[isabelmonteiro]

I did the test NS_PERIODIC similar to the EW UPWELLING test case, and everything works ok.
Further investigating my history file bathymetry I notice that bathymetry at E and W boundaries
are different from those of my grid file. I have a EASTERN wall and of course no problem there, but I have open western wall and problems arise there.
What am I doing wrong? How can the h matrix be different at history and grid file?

[isabelmonteiro]

To better show my problem with NS_PERIODIC, I've 3 figures with h. "Grid_bathy.jpg" is the bathymetry read from the grid file, "NS_periodic_his_bathy.jpg" is the bathymetry read from history file with NS_PERIODIC boundary conditions where the wrong h appears at Western and Eastern boundaries and finally "without_NS_periodic_his_bathy.jpg" is the bathymetry read from history file without NS_PERIODIC boundary conditions with no problem with the h at the boundaries

Somehow in this forum I can't attach files (maybe no permissions?) but if you allow me I can show you the different bathymetry at history files depending of boundary conditions