I have a fully 2D simulation (version 5.0.7) that estimates significantly different results depending on whether diffusion wave or full momentum equations are used. If I take the time to orient the cell faces within the main channel perpendicular to flow, the full momentum results better match the diffusion wave results. When modeling channel reaches with 2D elements, should I be orienting cells in the direction of flow? Thanks.
Thanks cameron. I’ve been using breaklines to orient the cells perpendicular to flow, which can be time consuming in a large model. Any other methods to recommend? Doesn’t look like there is an option to orient cells within a refinement region, correct? What about the ‘Generate as Hexagon’ feature in the refinement region properties table? That option seems promising, but checking that box didn’t appear to make any changes to the mesh. Thanks.
I usually use breaklines either along the banks or one down the center of the channel. There is other software that can create meshes for HEC-RAS which have better meshing options and you can orient the cells.