Is it a must to use VolCons if RadNud activated?

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corvianawatie
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Is it a must to use VolCons if RadNud activated?

#1 Unread post by corvianawatie »

Dear all,
I want to know, if is it a must activate the VolCons if I am using RadNud boundary condition for 3D U,V,T,and S?
I have 4 open boundary conditions, with boundary value from reanalysis ocean model. And I am forcing the model with surface heat flux, freshwater flux (calculated using bulk fluxes). And in the next, I will add wind stress, and I won't use tidal forcing. Maybe anyone can help me to explain how the VolCons doing in the boundary?

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!
!                   W       S       E       N
!                   e       o       a       o
!                   s       u       s       r
!                   t       t       t       t
!                           h               h
!
!                   1       2       3       4

   LBC(isFsur) ==   Cha     Cha     Cha     Cha         ! free-surface
   LBC(isUbar) ==   Fla     Fla     Fla     Fla         ! 2D U-momentum
   LBC(isVbar) ==   Fla     Fla     Fla     Fla         ! 2D V-momentum
   LBC(isUvel) ==   RadNud  RadNud  RadNud  RadNud      ! 3D U-momentum
   LBC(isVvel) ==   RadNud  RadNud  RadNud  RadNud      ! 3D V-momentum
   LBC(isMtke) ==   Gra     Gra     Gra     Gra         ! mixing TKE

   LBC(isTvar) ==   RadNud  RadNud  RadNud  RadNud \    ! temperature
                    RadNud  RadNud  RadNud  RadNud      ! salinity

! Adjoint-based algorithms can have different lateral boundary
! conditions keywords.

ad_LBC(isFsur) ==   Per     Clo     Per     Clo         ! free-surface
ad_LBC(isUbar) ==   Per     Clo     Per     Clo         ! 2D U-momentum
ad_LBC(isVbar) ==   Per     Clo     Per     Clo         ! 2D U-momentum
ad_LBC(isUvel) ==   Per     Clo     Per     Clo         ! 3D U-momentum
ad_LBC(isVvel) ==   Per     Clo     Per     Clo         ! 3D V-momentum
ad_LBC(isMtke) ==   Per     Clo     Per     Clo         ! mixing TKE

ad_LBC(isTvar) ==   Per     Clo     Per     Clo \       ! temperature
                    Per     Clo     Per     Clo         ! salinity

! Set lateral open boundary edge volume conservation switch for
! nonlinear model and adjoint-based algorithms. Usually activated
! with radiation boundary conditions to enforce global mass
! conservation, except if tidal forcing is enabled. [1:Ngrids].

   VolCons(west)  ==  F                           ! western  boundary
   VolCons(east)  ==  F                           ! eastern  boundary
   VolCons(south) ==  F                           ! southern boundary
   VolCons(north) ==  F                           ! northern boundary

ad_VolCons(west)  ==  F                            ! western  boundary
ad_VolCons(east)  ==  F                            ! eastern  boundary
ad_VolCons(south) ==  F                            ! southern boundary
ad_VolCons(north) ==  F                            ! northern boundary
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kate
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Re: Is it a must to use VolCons if RadNud activated?

#2 Unread post by kate »

I never, ever use VolCons. If you have the Flather boundary condition, the model should not fill or drain excessively - unless of course the zeta boundary conditions you give it suggest that it should fill or drain excessively.
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corvianawatie
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Re: Is it a must to use VolCons if RadNud activated?

#3 Unread post by corvianawatie »

Thank you Kate.
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venuscheung

Re: Is it a must to use VolCons if RadNud activated?

#4 Unread post by venuscheung »

I would like to change my boundary condition too

LBC(isFsur) == Clo Cha Cha Cha ! free-surface
LBC(isUbar) == Clo Fla Fla Fla ! 2D U-momentum
LBC(isVbar) == Clo Fla Fla Fla ! 2D V-momentum
LBC(isUvel) == Per Clo Per Clo ! 3D U-momentum
LBC(isVvel) == Per Clo Per Clo ! 3D V-momentum
LBC(isMtke) == Per Clo Per Clo ! mixing TKE

however, it gives out error
I also modified my .h file.
Attachments
upwelling.h
(2.37 KiB) Downloaded 205 times
run.log
(75.62 KiB) Downloaded 220 times
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kate
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Re: Is it a must to use VolCons if RadNud activated?

#5 Unread post by kate »

It's blowing up at point 2, 13, 8. Your Courant numbers are getting rather large, so you might start by trying a shorter timestep. You could also look at the fields it has saved for you in the restart file.

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       122 2018-01-01 20:20:00.00  3.461952E-03  7.113528E+02  7.113563E+02  5.699591E+12
                     (002,013,10)  1.679782E-01  1.956149E+00  1.810685E+00  4.047855E+00
       123 2018-01-01 20:30:00.00  4.049395E-03  7.113517E+02  7.113557E+02  5.699581E+12
                     (002,012,08)  1.643369E+00  4.621281E+00  6.603845E+00  1.164080E+01
       124 2018-01-01 20:40:00.00  5.038083E-02  7.113511E+02  7.114015E+02  5.699570E+12
                     (002,013,08)  6.699952E+00  5.775705E+01  1.952329E+01  1.316330E+02
 DIAG speed trouble    131.633017309940     
 DIAG speed ijk    178.759582292795                2          13           8
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wilkin
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Re: Is it a must to use VolCons if RadNud activated?

#6 Unread post by wilkin »

You can't mix Periodic and Closed on the same boundary for different variables.
Lateral Boundary Conditions: NLM
============================

Variable Grid West Edge South Edge East Edge North Edge
--------- ---- ---------- ---------- ---------- ----------

zeta 1 Closed Chapman Imp Chapman Imp Chapman Imp

ubar 1 Closed Flather Flather Flather

vbar 1 Closed Flather Flather Flather

u 1 Periodic Closed Periodic Closed

v 1 Periodic Closed Periodic Closed

temp 1 Periodic Closed Periodic Closed

salt 1 Periodic Closed Periodic Closed

If it's periodic for one it only makes sense to be periodic for all.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
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venuscheung

Re: Is it a must to use VolCons if RadNud activated?

#7 Unread post by venuscheung »

I have turn the timestep from 600 to 60 seconds but still there are error
ROMS/TOMS - Blows up ................ exit_flag: 1
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wilkin
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Re: Is it a must to use VolCons if RadNud activated?

#8 Unread post by wilkin »

Look at the log file report on the grid ...
ANA_GRID - bathymetry at RHO-points: h
(Grid = 01, Min = 0.00000000E+00 Max = 0.00000000E+00)
The water depth is zero everywhere!

Which explains why the vertical grid spacing is zero ...
Metrics information for Grid 01:
===============================
...
Minimum Z-grid spacing, DZmin = 0.00000000E+00 m
Maximum Z-grid spacing, DZmax = 0.00000000E+00 m
and the grid stiffness ratios are singular ...
Maximum grid stiffness ratios: rx0 = NaN (Beckmann and Haidvogel)
rx1 = NaN (Haney)
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu
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venuscheung

Re: Is it a must to use VolCons if RadNud activated?

#9 Unread post by venuscheung »

wilkin wrote: ↑Fri Nov 15, 2019 3:01 pm Look at the log file report on the grid ...
ANA_GRID - bathymetry at RHO-points: h
(Grid = 01, Min = 0.00000000E+00 Max = 0.00000000E+00)
The water depth is zero everywhere!

Which explains why the vertical grid spacing is zero ...
Metrics information for Grid 01:
===============================
...
Minimum Z-grid spacing, DZmin = 0.00000000E+00 m
Maximum Z-grid spacing, DZmax = 0.00000000E+00 m
and the grid stiffness ratios are singular ...
Maximum grid stiffness ratios: rx0 = NaN (Beckmann and Haidvogel)
rx1 = NaN (Haney)
I see the problem.
However, if I change nothing to the boundary conditions, the file can be run sucessfully.
Also, I cant see any problem in my bathymetry file
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