Tute M04 QGIS 1d bc Archive

From Tuflow
Jump to navigation Jump to search

Introduction

In this section we will create the 1D boundary conditions layer using a TUFLOW 1d_bc file. It is in this layer that we will specify the 1D boundary conditions.

Method

  1. Open the 1d_bc_empty_P.shp template file from the TUFLOW\model\gis\empty folder. Save this template file as 1d_bc_M04_001_P.shp in the TUFLOW\model\gis folder.
  2. Check the 'add saved file to map' box when saving the new layer or alternatively load the new layer to the current view. Toggle editing for the new layer. The template file may now be closed.
  3. We are going to snap three point features to the 1d_nwk_M04_channels_001_P layer, providing the necessary upstream and downstream boundaries to the creek channel. With snapping enabled in QGIS, use the Add Feature tool to digitise a point feature snapped to the upstream extent of the 1d_nwk_M04_channels_001_P layer (the south western area of the model area).
  4. In the attributes window that is displayed, enter the point Type as QT and the Name as FC01. Make all other attributes blank by removing any null entries. The name FC01 links the boundary condition specified in the bc_database to this location in the model.

  5. Tute M04 QGIS 1d bc 01.png

  6. Repeat this process and digitise a point feature snapped to the upstream extent of the secondary channel FC02. Again specify the boundary Type as QT and this time the Name as FC02. This name will link channel FC02 to the unique inflow boundary in the bc_database.
  7. To complete the process we need to specify the boundary condition to be connected to the downstream extent of the model located to the north. Digitise a point feature snapped to the downstream extent of the 1D channel at ds_weir. The downstream boundary is an water level versus flow boundary that assigns a water level at the downstream boundary according to the flow entering the node. Specify the Type as HQ and the Name as DS_BC.
    Tute M04 QGIS 1d bc 02.png

  8. Save edits to the 1d_bc_M04_001_P layer to finish.

Conclusion

The 1d_bc layer is now ready for input into TUFLOW. Please return to the Module 4 main page here where the next step is to create modified TUFLOW simulation control files prior to running the model.