Detailed Description

This directory exercises the optional four-equation UAWSoM extension in the ordinary MHD module. The four parameter combinations test:

1. propagation direction and periodic conservation without effective sources;
2. conservative wAplus/wAminus exchange from the Eq. 34 reflection term;
3. nonlinear Alfvén and kink damping, with lost wave energy recovered as heat because total energy is conserved; and
4. repair of a negative wave energy by the standard small-value mechanism.

Run all short cases with make -f test.make. Regression logs use the common MPI-AMRVAC tolerances (relative 1e-5, absolute 1e-8).