Discretisation changes for RT-DG pair: - #465
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stephankramer
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- In the pressure gradient term, the jump term disappears because the velocity (test) space is hdiv. Avoid adding it to UFL and relying on firedrake to figure out it cancels - i.e. this code change does not change the numerics
- Because we have no Roe flux in the pressure gradient term, it's more consistent to not have it in the HUDiv term either. The only reason we need a jump term at all is because of the discontinuity in H in the nonlinear approximation only, i.e. we're not weakly imposing a linearized Riemann condition at the cell boundary. Having this term negatively affects the accuracy of low order RT-P0
* In the pressure gradient term, the jump term disappears because the velocity (test) space is hdiv. Avoid adding it to UFL and relying on firedrake to figure out it cancels - i.e. this code change does not change the numerics * Because we have no Roe flux in the pressure gradient term, it's more consistent to not have it in the HUDiv term either. The only reason we need a jump term at all is because of the discontinuity in H in the nonlinear approximation only, i.e. we're not weakly imposing a linearized Riemann condition at the cell boundary. Having this term negatively affects the accuracy of low order RT-P0
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Fix RT/BDM-DG1 cases for this test (without the jump(eta) term in HUDiv)
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It's not a stringent test and duplicates test/swe2d/test_steady_state_basin_mms.py
Add a bit more damping in steady state channel mms test. Fix viscosity in steady state channel mms test.
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