Output files

Regular Mesh Output (ASCII Text)

The output files are written to the “Results” directory. If non-existant, this folder is created during cmake run. The results are printed at the timestep defined in the Master Configuration file (variable PRINT_STEP, in seconds, e.g., 1h = 3600 seconds). The results are saved in ASCII files; one file for each time step (with the file name being the time in seconds). The basic time unit in the model is seconds. The results are printed in each column are (in order):

irow [-]	row number of cell
icol[-]	column number of cell
z [m]	water elevation above sea level (with reference to the DEM)
h [m]	water depth
ux [m/s]	velocity in the x direction
uy [m/s]	velocity in the y direction
qx * dxy [m3/sec]	flow in the x direction
qy * dxy [m3/sec]	flow in the y direction
us [m/s]	sheer velocity
conc_SW [mg/l]	concentration of solute in water
fe_1 [m2/s]	flow in the x direction
fn_1 [m2/s]	flow in the y direction
twetimetracer [sec]	wet time for each cell

See Supporting Scripts for visualization tools including the Google Earth KML exporter, VTK conversion, and more.

Triangular Mesh Output (VTK XML Unstructured Grid)

When using the triangular mesh (MESH_TYPE: "triangular"), output is written in VTK XML Unstructured Grid format (.vtu), which can be visualized in ParaView.

File Structure:

fluxos_out/
├── 3600.vtu                    # Timestep at 3600 seconds
├── 7200.vtu                    # Timestep at 7200 seconds
├── 10800.vtu                   # Timestep at 10800 seconds
├── ...
└── fluxos_timeseries.pvd       # ParaView time series collection

Cell-Centered Data Arrays:

Each .vtu file contains the triangular mesh geometry (vertices and cells) along with the following cell-centered data arrays:

Array Name	Units	Description
h	m	Water depth
z	m	Water surface elevation
zb	m	Bed elevation
ux	m/s	Velocity in x direction
uy	m/s	Velocity in y direction
velocity_magnitude	m/s	\(\sqrt{u_x^2 + u_y^2}\)
qx	m2/s	Unit discharge in x direction
qy	m2/s	Unit discharge in y direction
us	m/s	Shear velocity
conc_SW_0	mg/l	Solute concentration (species 0)
twetimetracer	s	Wet time tracer
cell_area	m2	Cell area

PVD Time Series File:

The .pvd file is a ParaView Data collection file that links all timestep .vtu files into a time series for animation and temporal analysis:

<?xml version="1.0"?>
<VTKFile type="Collection" version="0.1">
  <Collection>
    <DataSet timestep="3600.0" file="3600.vtu"/>
    <DataSet timestep="7200.0" file="7200.vtu"/>
    ...
  </Collection>
</VTKFile>

Open the .pvd file in ParaView to load all timesteps as an animation.

See Supporting Scripts for visualization tools including the Google Earth KML exporter, ParaView workflows, and more.