Error when changing boundaries for an idealized river plume

[fengfengsister]

Dear all,
I am now running a test case of an idealized river plume.
When I set the boundary conditions as follow,
west-Clo,south-Gra,east-Clo,north-Gra
The current field in the first layer on the 12.25 day is shown as figure1 in the attachment figures.docx

I want to change the east boundary to open boundary,so I set the following boundary condtions:

1.west-Clo,south-Rad,east-Rad,north-Rad
The current field in the in the first layer on the 12.25 day is shown as figure2 in the attachment figures.docx
The current at the south boundary is not what I want to see.

I also tried the following conditions, but the currents are not right either.

2. west-Clo, south-Rad,east-Gra,north-Rad
3. west-Clo, south-Rad,east-Clo,north-Rad
4. west-Clo, south-Gra,east-Gra,north-Gra
5. west-Clo, south-Per,east-Rad,north-Per

What is the problem?

My riverplume2.h file are as follow:

/*
** svn $Id: riverplume2.h 585 2012-01-03 18:44:28Z arango $
*******************************************************************************
** Copyright (c) 2002-2012 The ROMS/TOMS Group **
** Licensed under a MIT/X style license **
** See License_ROMS.txt **
*******************************************************************************
**
** Options for River Plume example by Hyatt and Signell described at
** http://smig.usgs.gov/SMIG/features_0300 ... nline.html
**
** Application flag: RIVERPLUME2
** Input script: ocean_riverplume2.in
*/

#define UV_ADV
#define UV_COR
#define UV_QDRAG
#define UV_PSOURCE
#define DJ_GRADPS
#define TS_A4HADVECTION
#define TS_A4VADVECTION
#define TS_DIF2
#define MIX_GEO_TS
#define TS_PSOURCE
#define NONLIN_EOS
#define SALINITY
#define MASKING
#define SOLVE3D
#define SPLINES
#define AVERAGES
#define SPONGE
#define RADIATION_2D


#define LMD_MIXING
#ifdef LMD_MIXING
# define LMD_RIMIX
# define LMD_CONVEC
# define LMD_SKPP
# define LMD_BKPP
# define LMD_NONLOCAL
#endif

#define ANA_GRID
#define ANA_INITIAL
#define ANA_PSOURCE
#define ANA_SMFLUX
#define ANA_SRFLUX
#define ANA_SSFLUX
#define ANA_STFLUX
#define ANA_BSFLUX
#define ANA_BTFLUX

Who can help me? Thank you.

My .in file is also attached.

[LiuZHQ]

I think, that periodic OBC for southern and northern boundaries should be better than the others. You may want to extend your grid southward.

Regards,
ZQ

[fengfengsister]

I think, that periodic OBC for southern and northern boundaries should be better than the others. You may want to extend your grid southward.

Regards,
ZQ

Thank you ZQ for you replying.

But I have already try the following boundary conditions:
1. The west and east boundaries are solid ones, and the current field shown in the attachment; The result is not I want.

2. I also set the east boundary as Radiation boundary condition, and other boundaries do not change just like "1".
But the result is also wrong.

Regards,

[LiuZHQ]

Since the plume propogates very fast along the coastline, and it can easily reach the southern boundary in several days. Perodic OBC brings the plume into your domain through northern boundary, which contaminant your solution. That's why I suggest you extend the domain to the south.

Regards,
ZQ

[fengfengsister]

Since the plume propogates very fast along the coastline, and it can easily reach the southern boundary in several days. Perodic OBC brings the plume into your domain through northern boundary, which contaminant your solution. That's why I suggest you extend the domain to the south.

Regards,
ZQ

Thank you so much for your replying. It is very kind of you to explain what "extend your grid sothward " or "extend the domain to the south " mean? I am not following you.

Best wishes,
Daifeng

[LiuZHQ]

I mean, you may want to increase the length of your domain to the south by adapting more grids. So that, the southern boundary will be far away from the river mouth to prevent that contaminantion from Periodic OBCs.

regards,
ZQ