Ww3 diffraction

[aronroland]

Pull Request Summary

wave diffraction following (DOI:10.1016/S0378-3839(03)00065-6).

Description

This enhancement implements wave diffraction based on the MSE within the WW3 model on unstructured grids. WA Gradients are evaluated using linear shape function. Introduces non-linear propagation based on amplitude dispersion, since all advection velocities become function of the solution itself (total fun). This changes basically the whole nature of the scheme in terms of math and numerics. Certain experiences will be necessary and it is an active development. We will add also DOI:10.1016/j.coastaleng.2011.01.002; rudimentary also already included). The latter work improves the solution in the presence of strong shearing currents. The introduced data structures provide also the basis to include non-linear dispersion as suggested by Marten Dingemans and furthermore the redefinition of the conserved quantity based on the work of Staissnie et al. and Toledo et al.. It must be here remarked that wave action is not a conservative variable in the presence in non-homogenous media. See also Willebrand (JCP). However, the most remarkable work is given by Staissnie. This all touches the same issue.

Please also include the following information:

• Add any suggestions for a reviewer
  Have fun!
• Mention any labels that should be added: bug, documentation, enhancement, new feature
  enhancement
• Are answer changes expected from this PR? Please describe the changes and the reason why in addition to which of the following labels would apply: mod_def change, out_grd change, out_pnt change, restart file change, Regression test
  No!
  -->

Issue(s) addressed

It provides the needed data structures for #937 and introduces the needed work for #931

Commit Message

wave diffraction on unstructured grids.

Check list

• [ X] Branch is up to date with the authoritative repository (NOAA-EMC) develop branch.
• [ X] Checked the checklist for a developer submitting to develop.
• If a version number update is required, checked the updating version number checklist.
  Yes
• If a new feature was added, a regression test for testing the new feature is added.
  Pending, will be decided by our team.

Testing

• How were these changes tested?
  Different cases.
• Are the changes covered by regression tests? (If not, why? Do new tests need to be added?)
  See above.
• Have the matrix regression tests been run (if yes, please note HPC and compiler)?
  Will be done by ERDC
• Please indicate the expected changes in the regression test output, (Note the list of known non-identical tests.)
  None
• Please provide the summary output of matrix.comp (matrix.Diff.txt, matrixCompFull.txt and matrixCompSummary.txt):
  Pending.