Getting Started – 1D Modelling
This document provides a ‘quick start guide’ for new users of Flood Modeller showing how to run a 1D model and view results.
The guide uses the example files provided with Flood Modeller. Depending on your operating system these are located at:
• “C:\Users\Public\Documents\Flood Modeller\Getting Started” for Windows Vista/7/8 (may be accessed from Libraries\Documents)
• “C:\Documents and Settings\All Users\Documents\Flood Modeller\Getting Started” for Windows XP Note that the example data are solely design to demonstrate the Flood Modeller software – they are based on hypothetical or old data sets and should not be used in decision making.
To run a 1D model in Flood Modeller follow the steps below:
1. Start Flood Modeller and on the Home tab of the main toolbar click Load 1D Network
Browse to “…\Getting Started\1D Model”, select the Example1D.dat file and click Open to load the model network into the interface.
The model network should be automatically loaded into your map view, showing the river cross sections and two boundary nodes.
2. Load background map data. Different background data can be used depending on whether you have an internet connection available.
If you are connected to the internet you can utilise freely available online mapping data via a web mapping service (WMS). You can load a WMS “layer” into your Flood Modeller map view and the software will automatically request the most appropriate background mapping based on your location and zoom level. The example data includes a WMS layer, to load this:
• Click Add GIS Data button in the Home tab of the toolbar
• Browse to “…\Getting Started\1D Model”, select the OpenStreetMap.wms file. Note that this may take a few seconds to load (depends on the speed of your internet connection). Furthermore you may need to pan or zoom your map view for it to refresh with the background data visible. If you do not have access to the internet (or your connection restricts downloading) you can load the background map image provided in the example folder:
• Click Add GIS Data button in the Hometab of the toolbar
• Browse to “…\Getting Started\1D Model”, select the BackgroundMap.png file and click Open. Note that this is a low resolution image.
Getting Started – 1D Modelling Flood Modeller • In either the Mapview or Network Panel, select the HTBDY unit 3.38 (HTBDY is shorthand for Head
Time Boundary) located at the east of the network (bottom of the list in the Network panel). Right click and select 1D Node Properties to show the data associated to the selected node.
• Click the Plot button in the node properties window. This will display (in a new window) a plot of water level vs time for the downstream boundary condition of your model. You should be able to see that the downstream boundary condition for this model is of a tidal nature, as in the image below. After inspecting these data close the chart window and close the node properties window.
4. View one of the cross sections. To do this, select one of the river section units (for example section 2.12), right click and select Cross Section and click the plot button. You should see the cross-sectional profile of the selected river node. Close the plot.
5. Run the simulation. This can be done either by clicking on the “New 1D Simulation” button in the Simulation Tab of the main ribbon. You will be prompted to specify a name and location for saving your simulation file, eg ‘example1d’. A simulation run definition window will then appear, as shown below.
6. Select “Unsteady (Fixed Timestep)” as your run type, set the “Finish time” to 36 hours and set both the “Timestep” and “Save interval” to 360 seconds. Click Run to start your simulation.
Getting Started – 1D Modelling Flood Modeller 7. View the results.
First let’s view the water level time series at one of the river sections. It should be a tide graph similar (but not identical) to the downstream boundary condition shown previously. To do this, select a river section (either on the map or in the Network panel, e.g. node 2.26), right-click and select “Time Series” from the displayed options. A new window is displayed which enables you to specify a results file, a node from the associated network, a start and end time and a parameter to plot. Leave all settings to their defaults and click the “Plot” button. The water level (stage) result at the node you selected will be plotted, as shown below (close the plot once you have looked at it).
Next, watch a dynamic animation of the changes in water level with time on a longitudinal profile of the river. To do this:
• Select all river section units either within the map view (by dragging across your network with the left mouse button depressed) or in the Network panel (by selecting the first unit in the model (node 2.1) and then scrolling down to the end of the nodes list (node 3.38) and pressing the <Shift> key and left mouse button together).
• Right mouse click on the highlighted sections and choose “Long Section”. A new window is displayed which enables you to specify a range of nodes from the active network. Your selection will already be specified here so click the “Plot” button to see the long section.
• Right click on the plot and select “animation” from the displayed options. The animation toolbar will appear at the top of the long section plot window.
• Click the “Play” button, and an animated sequence of your water level results will be displayed, as shown by the snapshot below:
The figures below illustrate the changes of water level in the river over the course of the simulation. You can see the changes of the tidal cycle along the river.
