FMA Challenge 1 (1D-2D linked): Difference between revisions
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Within the *.trd file the variables 2D_CELL_SIZE, 2D_Timestep and LogInt are set as scenario dependent variables.
When the model is initialised these variable values are inserted within the tcf and tgc file using the << >> syntax. i.e. For the 10ft scenario, <<2D_Timestep>> in the tcf is replaced with the value 10 as defined in the trd file.
Upon examination of the results, the flood extents varied by unexpected amounts between different resolutions. For example, the 10ft grid scenario (provided as part of the ftp download) produces a more extensive flood extent, even though the profile down the 1D channel is almost identical to the 15ft case. The extended flooding is the result of very shallow flow (less than 0.01ft deep) over large flat (horizontal) areas caused by the use of contours to create the DEM as discussed above. Due to the slightly coarser resolution the 15ft grid does not let water on to some of these flats, and they remain dry. Should an accurate DEM be made available for this Challenge, the flood extents are likely to be very different and much more consistent between different grid resolutions!
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