Product(s):	OpenFlows FLOOD
Version(s):	10.03.XX.XX
Area:	Modeling

Overview

This article describes the main necessary steps to set up a simulation that reads a pre-computed hydrodynamic solution using OpenFlows FLOOD's MOHID Water engine. This enables to the engine to run some applications reading an existing hydrodynamic solution without having to compute it again saving a lot of time. Examples of applications where this methodology is used are, for example, simulating oil spill scenarios or wastewater dispersion, where the hydrodynamics is read from a file and used by the Lagrangian transport model to transport the Lagrangian particle tracers.

Solution

To read a pre-computed hydrodynamic solution go the Hydrodynamic model and set the following options:

Alternatively, you can use the text editor options as shown below: 

EVOLUTION                         : Imposed Solution

<begin_waterlevel>
NAME                                   : water level
UNITS                                   : m
DIMENSION                         : 2D
DEFAULTVALUE                  : 0
FILE_IN_TIME                      : HDF
FILENAME                            : ..\General Data\Solution\Hydrodynamic_1.hdf5
<end_waterlevel>

<begin_velocity_u>
NAME                                   : velocity U
UNITS                                   : m/s
DIMENSION                         : 2D
DEFAULTVALUE                  : 0
FILE_IN_TIME                      : HDF
FILENAME                            : ..\General Data\Solution\Hydrodynamic_1.hdf5
<end_velocity_u>

<begin_velocity_v>
NAME                                   : velocity V
UNITS                                   : m/s
DIMENSION                         : 2D
DEFAULTVALUE                  : 0
FILE_IN_TIME                      : HDF
FILENAME                            : ..\General Data\Solution\Hydrodynamic_1.hdf5
<end_velocity_v>

 

Keep in mind that when reading an imposed hydrodynamic solution the following settings must be set and the following assumptions are made:

1) The computational horizontal grid and vertical discretization of the simulation must be the same used in the computation of the solution that is going to be read from an HDF5 file. 

2) The user should remove any options related with computing vertical turbulence in the Turbulence model and transport of water constituents in the WaterProperties module

3) The time step defined in the Model options can be increased to values lower or equal to the time frequency of the HDF5 being read, e.g. if the HDF5 file was saved every 10 minutes, your model time step can now be 10 minutes (600 seconds) or less. 

4) If the solution that is being read from an HDF5 file was not generated by OpenFlows FLOOD's MOHID Water engine, make sure that point 1) in this list is verified and make sure that the values being read are correct and in the same units as the MOHID Water engine uses (I.S. units - kg, meters and seconds)