How to define new event data for a 1D model

This section explains how to define and edit a new event data file for a 1D model simulation. The event data file in a 1D model is known as an IED file and it is used to facilitate setting up a range of model simulations using a single, baseline 1D network.

Event files are text files that contain one or multiple 1D model nodes defined using the same format as used in 1D network files (dat files). The event files are not standalone networks though as they only contain the node parameters and not the associated network metadata. A 1D simulation can reference one or multiple event files.Then at runtime the event data will supersede that contained in the main 1D network for the referenced nodes.

For a model to be valid any units specified in event files must REPLACE a unit in the associated 1D network file, i.e. a unit of similar type with identical node label(s) must already exist in the DAT file. A QTBDY in the event data may replace a QTBDY or Hydrological boundary in the data file, for instance, but a Gated Weir may NOT replace another weir type, such as a Sharp-Crested Weir.

Defining a new event file

To define a new event data file you have 2 options:

1. Go to the project view in the upper left corner of Flood Modeller interface and right click on the Event Data section, you can then select to create a new file by choosing the option New Event File > Event Data File. There is also an option here to create a Section Data File. This will effectively also create an event format file. However it is common practice to store cross section data in an event file with extension ‘.sec’. Other than the file extension there is no difference between section and event files and Flood Modeller handles both in the same way.

   

   Note: You do not need to have an existing 1D network loaded in your project in order to create an event file in this way.

   The Event Data menu also enables you to load existing event data by selecting the option Add Item. You will be prompted to specify the location and name of the existing IED file to be added to your project.

2. Alternatively you can create a new event file as a subset of your active 1D network. First select a node (or nodes) from your active 1D network (in the map view or network or nodes tables). Right click on the network table and select File > Create event file from the displayed menu. The selected nodes will be exported to a new IED file, which will be automatically added to your project.

   

   Note: This option requires you to have a network loaded in your project. Furthermore the nodes that will make up the content of your event file must already be defined in your active network.

Editing an event file

Flood Modeller provides two methods for editing 1D event files. The optimum method for you will depend on the other content in your project and on how you want to edit your event file.

Full editing

You can edit 1D event files in the same way as 1D networks, i.e. add new nodes to either the map view or the network table (right hand panel).

Once the file is created make sure the item is active in the project view (right click on the item and select Set Active or just double click on the item). You can then proceed to insert the hydraulic or hydrological units required by clicking the appropriate icon in the 1D Build tab and then clicking on the map view (i.e. the same as creating a full 1D network). The nodes added to the active event file will be displayed in the map view and loaded into the network table (note that while an event file is active in the interface there will not be an active network).

The geographic positions of event file nodes are stored in an associated text file with extension ‘.pxy’ (which uses the same format as the 1D network gxy file). If you exported the units from a 1D network file then the event data file will not currently display these units in the same locations on the map view as in the full 1D network. However, you can utilise the Move Nodes function (on the map right-click menu) to re-position your event node locations (the new locations will be saved to the pxy file when you next save your event file).

You can edit the units in an active event file by double clicking on the units either in the map view or the Network panel (or by right clicking on a highlighted unit and selecting the edit 1D node properties option from the displayed menu).

The event data file can contain any of the following units:

• All channel units: RIVER, CONDUIT, INTERPOLATE, REPLICATE

• Bridges: ARCH and USBPR

• Weirs: CRUMP, RNWEIR, SCWEIR, WEIR, NTWEIR, FLAT-V, QH CONTROL, SYPHON

• ORIFICE

• SPILL

• CULVERT LOSSES: INLET, OUTLET and BEND units

Changes made to an active event file are saved in the same way as an active 1D network. Click the Save or Save As buttons in the Networks section of the main toolbar (Home tab).

Useful tip: An event data file can contain any number of units together within the same file. However, considering that a simulation file can contain up to 10 event files, it is recommended that you create a new IED file for each type of units in order to create a more organized model.

Partial editing

If the 1D network associated to your event file is large then it will take time to make the network active again after editing the event file using the above method. This is inefficient if you only need to review or edit the properties of an existing event node. An alternative editing option can be accessed from the event file right-click menu in the Project panel.

1. Load (or create) an event file in your project.

2. In the Event Data section of the Project panel right-click on the event file and select List Contents. Note the event file does not have to be active in the map when you do this.

   

3. A new window will be displayed that lists the event file content. Double-click on a unit to review. The associated unit property window will then be displayed (as if you were editing it in a 1D network). You can review the content and make any required changes.

   

4. Close the unit property window and then (if editing is complete) close the event file contents window (by clicking on the red “X” in the upper right corner). If you have made any changes you will be prompted to save your event file.

   Note: Although this method enables you to quickly edit an event file without first making it active, it will only allow you to edit properties of existing units within the file. This edit method does not allow you to add new nodes to your event file or to delete existing ones.

Event File Menu

Right-clicking on an event file loaded in the Project Panel will display a menu. This contains the following options:

• Set Active – Makes the selected event file active within the map, Network table and Nodes table. You can then add new units to the event file and edit, move or remove existing units. Only one network or event file can be active in the Flood Modeller interface at any time, so if you make an event file active then your network will no longer be active.

• List Contents – Displays a new window listing the content of the event file. You can double-click on any unit in the list to review or edit the associated properties (without the need to make the event file active in the map and tables).

• Remove – removes event file (reference) from your project (file is not deleted)

• Copy – Creates a copy of the event file, adds it to your project, but does not make it active in the interface (the current event file remains active)

• Properties – displays new window that displays the full path location of the event file and allows you to change the displayed name for the file within the current project (default is the filename). It also provides a free text entry to add any additional detail about the event file, e.g. data source, date created, author, etc. Changes made in this window will be saved as part of the current project.

Adding an Event file to your simulation

Event data file(s) added to your project can be easily incorporated into a 1D simulation file. The event data files to be used in a simulation are specified in a table in the files tab of the 1D simulation interface. You can either browse to add IED files (using the Add button next to the Event Data table) or you can add files from your project by dragging them from the Project panel into the table.

For a model to be valid any units specified in event files must REPLACE a unit in the associated 1D network file, i.e. a unit of similar type with identical node label(s) must already exist in the DAT file. A QTBDY in the event data may replace a QTBDY or Hydrological boundary in the data file, for instance, but a Gated Weir may NOT replace another weir type, such as a Sharp-Crested Weir.