- For most Riemann problems (Fig. 26) the CIR scheme (185) actually produces initially the exact result.
- Only for a transonic rarefaction wave (as in the last example in Fig. 30) it differs.
- Godunov's idea: Solve a Riemann problem ( Riemann solver) at every cell boundary and derive the corresponding flux over the boundary.
- For Burgers' equation the flux through the stagnation point () in a transonic rarefaction wave is .