Module Discharges
From MohidWiki
Contents
Overview
Module Discharges handles all the point discharges in Mohid Water Modelling System. These discharges can be simple water discharges but can also have properties such as substances concentration (temperature, salinity, nutrients, contaminants, etc) and/or momentum.
Main features
ID
Location
Horizontal
A discharge can be made in a point, along a line or in a polygon. The keyword to define the type of horizontal emission is SPATIAL_EMISSION, the options are: Point, Line and Polygon. The default option is Point.
SPATIAL_EMISSION : Point
A point can be define using the grid coordinates (COORD_X, COORD_Y)
COORD_X : 8.6 COORD_Y : 42.3
or specifing the cell (I_CELL - line, J_CELL - column)
I_CELL : 23 J_CELL : 43
To define a discharge along a line is necessary to specify a file with the Lines format. The keyword used is SPATIAL_FILE.
SPATIAL_FILE : Discharge.lin
To define a discharge in a box is necessary to specify a file with the Polygon format. The keyword used is SPATIAL_FILE.
SPATIAL_FILE : Discharge.xy
Vertical
VERTICAL_DISCHARGE - this keyword is used to specify the discharge distribution in the vertical direction:
1 – discharge in the bottom cell 2 – discharge in the surface cell 3 – discharge in the cell that intersects the depth defined in the keyword K_DEPTH (no default value). It is a depth relative to the water surface. 4 – discharge in the layer defined in the keyword K_CELL (no default value) 5 – Assumes a uniform distribution along the entire water column
Option 4 is the default one.
Database file
Properties
User manual
Sample discharge
MOHID WATER
Here's what a configuration file of the Module Discharges should look like for a single river run-off. Note that you are previously required to build a time serie .srw with the flow, the temperature and the salinity in order to correctly implement the discharge.
<begindischarge> NAME : Loire DESCRIPTION : Daily timeserie for the year 2004 I_CELL : 144 J_CELL : 220 K_CELL : 38 DEFAULT_FLOW_VALUE : 300 DATA_BASE_FILE : M:\Biscay\GeneralData\Level2\rivers\Loire.srw FLOW_COLUMN : 2 TIME_SERIE_COLUMN : 1 DISCHARGE_UNIFORM : 1 <<beginproperty>> NAME : temperature UNITS : celcius DESCRIPTION : temperature in the tagus river CONSTANT_CONC : 0 DEFAULTVALUE : 19.9 TIME_SERIE_COLUMN : 3 <<endproperty>> <<beginproperty>> NAME : salinity UNITS : psu DESCRIPTION : salinity in the tagus river CONSTANT_CONC : 1 DEFAULTVALUE : 0.01 <<endproperty>> <enddischarge>
MOHID RIVER NETWORK
For Mohid River Network discharges can be made on nodes. As so, you will need to check within the drainage network difinition in which node to discharge. Here's what a configuration file should look like for a single discharge. Note that you are previously required to build a time serie with the flow, and any other property in order to correctly implement the discharge.
Discharges into MOHID River Network can be automatically linked to SWAT model discharges; see description in SWATLink download package in www.mohid.com
Steps after creating the discharge time serie (with time and flow as minimum):
1 - Have to activate module discharges so that Discharges_X.dat in input data file appears in the simulation (in Simulation Properties add the model if not present)
2 - The block <begindischarge> <enddischarge> has to appear in Discharges_X.dat and can add the number of discharge properties that you want (or none, if only water discharged).
<begindischarge> NAME : NODE_19 DESCRIPTION : Not given NODE_ID : 19 DATA_BASE_FILE : ..\..\GeneralData\Discharge.dat FLOW_COLUMN : 2 <<beginproperty>> NAME : nitrate UNITS : mg N/l DESCRIPTION : nitrate TIME_SERIE_COLUMN : 3 <<endproperty>> ... <enddischarge>
To know the node ID of your discharge, do a query on the GIS, on top of the drainage network in the point required. The query result (if pointing to a river section) will say the node ID.
DATA_BASE_FILE is the file that was prepared with at least time and flow. If giving also property timeserie (e.g nitrate) also need a column to nitrate in the file. FLOW_COLUMN is the column with flow and TIME_SERIE_COLUMN is the column with the property time serie.
3 - have to activate discharges (DISCHARGES : 1) in DrainageNetwork_X.dat
4 - run the simulation and compare flow results in HDF or in node timeseries between a simulation with the discharge and without it (the discharge will only appear in the node timeseries results that are downstream of the inputed discharge).
