missing factors in hllc riemann solver (see Toro: (10.38), (10.39))

(cherry picked from commit b3f2463f)

I'm pretty sure there is a factor missing in the expressions for the momentum and energy flux of the HLLC riemann solver (when compared to Toro 2009, eqs. 10.38 and 10.39). It doesn't seem to have a noticeable impact on most hydro tests though...

added bug label

requested review from @mivkov

assigned to @yuyttenhove

added Gizmo label

Just double-checked the math. You are right, the factor is missing. Your MR should fix it appropriately. Thanks!

Did you find an example where you see a difference with the correct solver?

approved this merge request

@bvandenbroucke FYI.

approved this merge request

A have not looked into it too extensively, but the most noticeable difference I found was in a low resolution 1D first order (no gradient extrapolation) sod-shock test where the correct solver seems to resolve the rarefaction wave slightly better (most noticeable when switching between the images).

This is with the fixed solver:

And this with the old one: .

approved this merge request

assigned to @matthieu and unassigned @yuyttenhove

Do we need to fix any of the python tools in the plotting scripts? Or are these only solving the extra problem?

resolved all threads

merged

mentioned in commit 0b81dc53