How do I solve the simulation speed anomaly?

[zhaolv]

I was running roms and found that the model crashed at the fourth hour and prompted me with excessive speed at a certain point, I checked the rst file and found that there was indeed an exception, how do I fix this?
I have tried changing the model grid, the time step, but nothing has fixed the problem. Please can you help me.
Below is a screenshot of my logs file and rst results.

Code: Select all

                     (015,032,16)  8.993006E-04  1.060675E-03  2.194779E-01  2.871628E+00
      1127 2018-09-15 04:41:45.00  1.049570E-01  1.322309E+04  1.322319E+04  4.267362E+14  02
                     (015,032,16)  9.087804E-04  1.077216E-03  2.204331E-01  5.698030E+00
      FINE2COARSE - exchanging data between grids: dg = 02 and rg = 01  at cr = 02
       564 2018-09-15 04:42:00.00  1.207169E-01  1.518843E+04  1.518855E+04  1.468960E+15  01
                      (043,41,16)  5.148341E-04  1.923969E-03  1.325345E-01  4.506861E+01
 DIAG speed trouble    45.068605085211125     
 DIAG speed ijk    63.723548390533701               30          27           1           1
 Found Error: 01   Line: 341      Source: ROMS/Nonlinear/main3d.F
 Found Error: 01   Line: 331      Source: ROMS/Drivers/nl_ocean.h, ROMS_run

 Blowing-up: Saving latest model state into  RESTART file
     REASON: MaxSpeed =  4.5E+01

      WRT_RST     - wrote re-start    fields (Index=1,1) in record = 3                     01

 Blowing-up: Saving latest model state into  RESTART file
     REASON: MaxSpeed =  4.5E+01

      WRT_RST     - wrote re-start    fields (Index=1,2) in record = 3                     02

rst.png (25.69 KiB) Viewed 5508 times

[jcwarner]

what is the bathy in that corner?
i see you have
2 Vtransform S-coordinate transformation equation.
4 Vstretching S-coordinate stretching function.
5.0000E+00 theta_s S-coordinate surface control parameter.
4.0000E-01 theta_b S-coordinate bottom control parameter.
50.000 Tcline S-coordinate surface/bottom layer width (m) used
in vertical coordinate stretching.

not sure what that looks like in the vertical, but it might be tight vertical spacing in the shallow locations.

[zhaolv]

what is the bathy in that corner?
i see you have
2 Vtransform S-coordinate transformation equation.
4 Vstretching S-coordinate stretching function.
5.0000E+00 theta_s S-coordinate surface control parameter.
4.0000E-01 theta_b S-coordinate bottom control parameter.
50.000 Tcline S-coordinate surface/bottom layer width (m) used
in vertical coordinate stretching.

not sure what that looks like in the vertical, but it might be tight vertical spacing in the shallow locations.

I referred to other solutions to the problem and turned on the WET_DRY switch in the cpp and things got somewhat better.
But after I expanded the grid range, I ran it again and found some problems with the northern boundary.

rst_1.png (47.19 KiB) Viewed 5368 times

[jcwarner]

ok. if you min depth = 5 meters, and then wet/dry helped, i suggest you look at the zeta values to make sure the tides are ok. what is the tide range in this area?

for the next problem, that is probably a density issue. closely look at what is being put along that boundary for temp salt u v etc.

you need to dig into the output.
-j