HEC-RAS 6.6 previous release · 2D SWE-EM
HEC-RAS 6.6 2D with its Eulerian shallow-water option (SWE-EM), the release before 7.0.
Scored for compatibility with the current release, not for physics. Ran 7 tests; worked examples and previous releases are shown beside the leaderboard, not ranked on it. Score cards from: HEC-RAS 6.6 2D SWE-EM.
| Test | Difference, rank | Checks |
|---|---|---|
| Dam break onto dry ground A1F-010 | #12= 15 % off of 20 models | • Flood front 57.8 m behind exact; · Water conserved 0.0049 % error SWE-EM, the option HEC recommends for dam breaks, gets 40 m closer than the default SWE-ELM (58 m behind) but does not converge. |
| Dam break into shallow water A1F-011 | #12= 1.4 % off of 20 models | • Average depth error 7.7 mm off; · Water conserved 0.011 % error Error 8 mm, but it grows slightly on finer grids. |
| Steady flow over a shaped bed A2A-010 | #1= under 0.01 % off of 12 models | • Average depth error 0.062 mm off; · Water conserved 0.0039 % error As SWE-ELM: 0.06 mm, but the error levels off near 0.1 mm on finer grids (rate 1.02, 90 % range 0.43 to 1.60). |
| Flooding a cut-off pond A2C-EA1 | #7= 5.1 % off of 10 models | • Pond level, point 1 1.3 cm off; • Pond level, point 2 1.3 cm off; • Peak level 0.051 mm off |
| Filling floodplain hollows A2C-EA2 | #7= 0.72 % off of 10 models | • Water conserved 0.72 % off As SWE-ELM: HEC-RAS's own accounting shows a 1.4 % volume error. |
| Flood spreading over a floodplain A2C-EA4 | #1= under 0.01 % off of 10 models | • Water conserved 0.00088 % off |
| Valley flooding A2C-EA5 | #7= 0.044 % off of 10 models | • Water conserved 0.044 % off |