Proposed Changes

As an alternative to MARKER_HEATFLUX = (heat_flux_marker, q,... ), this PR adds MARKER_HEATTRANSFER = (heat_transfer_marker, h, Twall) to the list of wall boundary conditions where the wall heat flux is computed by q = h*(Twall-Tref). h is the heat transfer coefficient, Tref is to be set by default or by a further option.

@bigfooted Is this what you've been thinking of? If so, I'd go ahead adding this to the compressible and the heat solver as well, if not, we should get this right for the incompressible solver first :-)

PR Checklist

Put an X by all that apply. You can fill this out after submitting the PR. If you have any questions, don't hesitate to ask! We want to help. These are a guide for you to know what the reviewers will be looking for in your contribution.

• I am submitting my contribution to the develop branch.
• My contribution generates no new compiler warnings (try with the '-Wall -Wextra -Wno-unused-parameter -Wno-empty-body' compiler flags, or simply --warnlevel=2 when using meson).
• My contribution is commented and consistent with SU2 style.
• I have added a test case that demonstrates my contribution, if necessary.
• I have updated appropriate documentation (Tutorials, Docs Page, config_template.cpp) , if necessary.