High salinity discharge

MOHID Water forum. Questions and discussion around MOHID Water
anamartin98@gmail.com
MOHID User
Posts: 23
Joined: Thu Jan 01, 1970 00:00

High salinity discharge

Postby anamartin98@gmail.com » Wed Mar 30, 2011 08:59

Hi all
I'm trying to simulate a salinity discharge. I'm doing so by using the Lagrangian Module. The discharge is near shore (1 m deep) and without jets (it's a pipe buried under the beach pebbles). So I haven't used the MohidJet.

I've activated BOTTOM_EMISSION, ant the DEPTH_CELLS keyword is set to the deepiest (1, of 5 layers).

I've set an Eulerian_monitor (I suppose this is what let me see the salinity results in the grid, apart from the particles position).

This is my lagrangian archive

OUTPUT_TIME : 0 1200.
DT_PARTIC : 10
OUTPUT_CONC : 2

<BeginOrigin>
ORIGIN_NAME : EDAM
OLD : 0
GROUP_ID : 1
EMISSION_SPATIAL : Point
EMISSION_TEMPORAL : Continuous

FLOW : 0.313
FLOW_VARIABLE : 0
NBR_PARTIC : 3
ADVECTION : 1

POSITION_CELLS : 44 36
DEPTH_CELLS : 1
BOTTOM_EMISSION : 1
MOVEMENT : SullivanAllen
VARVELHX : 0.015
VARVELH : 0.03
TURB_V : Profile
COMPUTE_BUOYANCY : 1
!COMPUTE_PLUME : 1
DENSITY_METHOD : 2
!COEF_INITIAL_MIXING : 1

!TVOL200 : 3600.
!VOLUME_INCREASE : Double
!VOLFAC : 5e4

<<BeginProperty>>
NAME : salinity
UNITS : psu
CONCENTRATION : 72.5
DESCRIPTION : Salinidad vertido situacion actual
OUTPUT_HDF : 1
AMBIENT_CONC : 36.5
EULERIAN_MONITOR : D:\\MOHID_pruebas\\A01\\GeneralData\\SE2Boxes3D.dat
<<EndProperty>>

<<BeginProperty>>
NAME : temperature
UNITS : ºC
DESCRIPTION : temperatura vertido igual a ambiente
CONCENTRATION : 22
INITIALIZATION_METHOD : CONSTANT
OUTPUT_HDF : 1
AMBIENT_CONC : 22
EULERIAN_MONITOR : D:\\MOHID\\A01\\GeneralData\\SE2Boxes3D.dat
<<EndProperty>>

<EndOrigin>

And here go some questions:

-Why the salinity in the post processor results is centered in the upper layers and not in the deeper ones, if the density of the discharge is greater than ambient density? I've activated the COMPUTE_BUOYANCY keyword

-Should I simulate this type of discharge with 'Discharge Module' instead of Lagrangian Module? I've done this and the problem is that apparently, the salinity of the discharge is 'interpolated' in the whole cell and the initial salinity is 40psu, for example, instead of 72.5.

-How can I set TVOL200, VOLUME_INCREASE, and VOLFAC values for the Lagrangian particles in a salinity discharge like this one. Can anybody give me a bibliographic reference for this concept?

-And references for values for keywords for SullivanAllen option?


Thanks in advance
Ana

administrator@.
Site Admin
Posts: 349
Joined: Thu Jan 01, 1970 00:00
Location: Instituto Superior Tecnico - Lisbon - Portugal
Contact:

Postby administrator@. » Mon Apr 25, 2011 09:14

Hi,

The keyword EULERIAN_MONITOR does not exist. What exists is the EULERIAN_MONITOR_BOX which is used to monitor the eulerian results inside a box. You can use the keyword TIME_SERIE monitor the eulerian results in a grid cell.

BOTTOM_EMISSION is only used when the emission is from a box, not from a point source.

The DEPTH_CELLS : 1 places the emission at the top of the bottom grid cell.
If you're using a 2D model that's the water surface.

You can use the DEPTH_METERS option to place the exact depth of the discharge. Normally this bottom discharges are somewhere between 0.5 and 1 meters above the bottom.

You should do the simulation with a Lagrangian approach. If you do it in Eulerian you'll need a grid size that can simulate the processes of the discharge, meaning an extremely fine grid.

About TVOL200, etc these are actually calibration parameters. I'll check if there are references for this and post it back here.

Cheers,
Luis


Return to “MOHID Water”

Who is online

Users browsing this forum: No registered users and 7 guests