How to input river cross-section data in OpenFlows FLOOD


Product(s):OpenFlows  FLOOD
Version(s):10.XX.XX.XX
Area:Modeling

Problem

How to input river cross-section data in OpenFlows FLOOD?

Solution

Cross-sectional data for a river is required when running the 1D/2D River Coupling tool in OpenFlows FLOOD. This data needs to be imported in OpenFlows FLOOD in a specific file format. Currently OpenFlows FLOOD doesn't have an automatic tool to build or import cross-sections. However, the format of the cross-section file is a simple ASCII text file, so it can be created manually in a relatively straightforward way. If you have cross-sectional data available it can be input in a simple text file (using the Notepad application). Here is how you can do this;

For each river cross-section you need to create a "block" starting with <BeginCrossSection> and ending with <EndCrossSection>. Inside this block you need to add a keyword NAME to specify the name of the cross-section. For example something like, NAME : XS001

Now still inside the original <BeginCrossSection> / <EndCrossSection> you will need to add a second block beginning with <<BeginSectionValues>> and enfing with <<EndSectionValues>> within which you can define your cross-section points in a list format with X, Y and Z values. The order of the cross-section points is important, as the first value in the block must be the left river bank (direction of flow) and the last should be the right river bank. 

Here what the ASCII file should look like with 2 cross-sections defined

<BeginCrossSection>
NAME : XS001
<<BeginSectionValues>>
384287.4 248624.9 13.21
384283.1 248635.4 12.03
384282.7 248636.3 10.55
384281.2 248640.2 10.74
384279.4 248644.6 12.97
384279 248645.5 13.57
<<EndSectionValues>>
<EndCrossSection>

<BeginCrossSection>
NAME : XS002
<<BeginSectionValues>>
384189.1 248238.5 13.21
384187.8 248238.2 12.15
384183.2 248237.4 10.16
384180.8 248236.9 10.93
384180.3 248236.8 12.93
384180.3 248236.8 13.08
<<EndSectionValues>>
<EndCrossSection>

Once this cross-section data is prepared it can be read by OpenFlows FLOOD which will then generate a .dat file which is used for interpolating cross-sections during 1D-2D coupling between a 1D river and a 2D MOHID Land model. Keep in mind that currently (version 10.03.00.01) this tool only supports projected (metric) coordinates, thus the river cross-section points must defined in a projected coordinate system. 

See Also

OpenFlows FLOOD General FAQ's