2.3 Core architecture

TUFLOW CATCH provides three primary functions:

  • Coordination of the execution of TUFLOW HPC and TUFLOW FV across a whole-of-catchment domain (Hydrology and Integrated configurations)
  • Automatic geolocation and writing of flow and concentration boundary conditions for TUFLOW FV (as the receiving water model), generated from TUFLOW HPC predictions (as the catchment model) (Hydrology and Integrated configurations)
  • Pollutant export and transport calculations within a catchment (Pollutant Export and Integrated configurations)

The first of these is its core architectural capability and so is described here in Section 2.3.1. The latter two are technical componentry of this architecture and so are described in Sections 3.1 and 3.2, respectively.

2.3.1 Execution coordination

In Hydrology and Integrated configurations, TUFLOW CATCH overarches both TUFLOW HPC and TUFLOW FV to coordinate their execution to affect integrated numerical simulation of water and pollutant flows across a catchment and its receiving waters (the latter of which also includes water quality pollutant transformations). Whilst not undertaking equation solution itself, TUFLOW CATCH does coordinate these supporting TUFLOW products to do so in their respective domains, which are:

  • TUFLOW HPC: Surface and subsurface catchment hydrology and hydraulics, with or without pollutant export and transport
  • TUFLOW FV: Hydrodynamic, sediment transport, water quality and particle tracking (or user selectable module subsets/combinations thereof) receiving waterway modelling

The order of execution of TUFLOW HPC and TUFLOW FV, coordinated automatically under TUFLOW CATCH for each of the supported simulation configurations described in Section 1.3, is as follows.

2.3.1.1 Hydrology configuration

  1. Execute TUFLOW FV in test mode with the intention of
    1. Reading the TUFLOW FV model mesh and writing the associated mesh check file for subsequent use by TUFLOW HPC in its automatic geolocation processes
  2. Execute TUFLOW HPC, with the intention of
    1. Reading the TUFLOW FV mesh check files to determine the receiving water model domain location and extent
    2. Comparing this mesh with the TUFLOW HPC grid to then determine which TUFLOW HPC cells are to be designated as transfer cells where boundary conditions for TUFLOW FV are to be written (see Section 3.1) from TUFLOW HPC predictions
    3. Executing the TUFLOW HPC catchment based hydrologic and hydraulic modelling over the period specified
    4. Writing TUFLOW FV flow (and optionally constant and/or timeseries temperatures and salinities) boundary conditions at designated transfer cells
    5. Reporting map outputs such as water depth and velocity, as well as downstream timeseries of summed flows leaving the TUFLOW HPC domain
  3. Re-execute TUFLOW FV with the intention of
    1. Executing hydrodynamic receiving waterway modelling, using the flow (and optionally temperature and salinity) boundary conditions developed by TUFLOW HPC above
    2. Reporting receiving waterway simulation results such as flows and velocity fields

2.3.1.2 Pollutant export configuration

  1. Execute TUFLOW HPC, with the intention of
    1. Reading a user specified GIS polygon that defines the areal extents of the downstream receiving waterway
    2. Comparing this polygon with the TUFLOW HPC grid to then determine which TUFLOW HPC cells are to be designated as deactivated cells
    3. Executing the TUFLOW HPC catchment based hydrologic, hydraulic and pollutant export modelling over the period specified
    4. Reporting map outputs such as water depth, velocity, dynamic pollutant concentrations in the surface and/or subsurface domains, dry store evolutions and/or erosion/deposition zones (see Section 3.2) and downstream timeseries of summed flows and pollutant loads leaving the TUFLOW HPC domain through the user specified GIS polygon

2.3.1.3 Integrated configuration

  1. Execute TUFLOW FV in test mode with the intention of
    1. Reading the TUFLOW FV model mesh and writing the associated mesh check file for subsequent use by TUFLOW HPC in its automatic geolocation processes
    2. Reading the TUFLOW FV sediment transport and/or water quality log files to determine the suite of constituents to be simulated in the receiving waterway, and therefore those that require specification and simulation as exported (or constant and/or timeseries) pollutants in TUFLOW HPC
  2. Execute TUFLOW HPC, with the intention of
    1. Reading the TUFLOW FV mesh check files to determine the receiving water model domain location and extent
    2. Comparing this mesh with the TUFLOW HPC grid to then determine which TUFLOW HPC cells are to be designated as transfer cells where boundary conditions for TUFLOW FV are to be written (see Section 3.1) from TUFLOW HPC predictions
    3. Checking the pollutants specified in the pollutant export model for consistency with those set in the TUFLOW FV simulation
    4. Executing the TUFLOW HPC catchment based hydrologic, hydraulic and pollutant export modelling over the period specified
    5. Writing TUFLOW FV boundary conditions at designated transfer cells, including assignment of constant and/or timeseries pollutants in addition to those computed dynamically within TUFLOW HPC
    6. Reporting catchment based simulation results such as water depth, velocity, dynamic pollutant concentrations in the surface and/or subsurface domains, dry store evolutions and/or erosion/deposition zones (see Section 3.2) and downstream summed flows and pollutant loads leaving the TUFLOW HPC domain and entering the TUFLOW FV mesh
  3. Re-execute TUFLOW FV with the intention of
    1. Executing hydrodynamic, sediment transport, water quality and particle tracking (or user selectable module subsets/combinations thereof) receiving waterway modelling, using the boundary conditions developed by TUFLOW HPC above
    2. Reporting receiving waterway simulation results such as pollutant concentrations and diagnostic mass fluxes