Second-order Quadrilaterals (2D) meshes in standard Abaqus .inp format

[DanielDoehring]

This implements second-order 2D quadrilateral p4est meshes constructed from a standard-format Abaqus .inp files.
See #1847 for this feature request.

Essentially, this PR is a bunch of tedious mesh file parsing to extract the relevant information. As in the existing implementation, we focus on meshes constructed e.g. from gmsh which are exported to .inp format.

For validation, I ran the simulation of a laminar, low Machnumber (essentially incompressible) simulation over the SD7003 airfoil.

The averaged drag & lift coefficient are

Average drag coefficient: 0.049819536195680685
Average lift coefficient: 0.3817639249290595

which are in excellent agreement with reference data (See this preprint)

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 96.66667% with 7 lines in your changes missing coverage. Please review.

Project coverage is 96.37%. Comparing base (f09a707) to head (06494ee).

Files with missing lines	Patch %	Lines
src/meshes/p4est_mesh.jl	96.41%	7 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2217      +/-   ##
==========================================
- Coverage   96.37%   96.37%   -0.00%     
==========================================
  Files         486      487       +1     
  Lines       39186    39374     +188     
==========================================
+ Hits        37764    37945     +181     
- Misses       1422     1429       +7     

Flag	Coverage Δ
unittests	96.37% <96.67%> (-<0.01%)	⬇️

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[sloede]

This implements second-order 2D quadrilateral p4est meshes constructed from a standard-format Abaqus .inp files.

This is so awesome! Thanks a lot for this very cool feature 💪♥️

[andrewwinters5000]

Thanks for adding this feature! Overall the new file reading and constructors look good. I just left some questions about naming and future functionality.

[andrewwinters5000]

I would prefer to say curved here. My main reason is that this is the word used in the HOHQMesh and other software (like NekMesh) documentation to discuss the high-order boundary information. I have never encountered anyone referring to it as polygonal. Also, "polygonal" here makes it sound like you are representing the boundary information with polygons, which is not what is happening.

[DanielDoehring]

I see your point. I thought it might make sense to note the difference between the higher-order elements without a mapping and those with a mapping, where only the latter are truly curved, while the other are piece-wise linear in some way.
Does this make sense?

[andrewwinters5000]

Again, I would prefer to call the boundaries curved rather than polygonal. I already mentioned two reasons above. Another is that it over complicates the nomenclature. I think you want to use "polygonal" to clarify that the boundary is a closed, simply connected region with some number of sides (that are possibly individually curved). That is, some segments of the polygon can be straight-sided, attached to a spline and then attached to circular arc. This is why I think the catch all term of "curved" is better because it encompassed all these cases (as well as dimensions).

After all, one could say that a simple straight sided box domain has "polygonal boundary information" for the same reasons, but people would think I am weird to refer to a Carteisan box in this way :)