[OLAF] Implementation of a source panel method

[ebranlard]

This pull request is a draft

Feature or improvement description

• Adds source panels to OLAF to model walls, and bodies of arbitrary shapes, provided they are not moving or being deformed elastically.
• Allows the AeroDyn driver to be run with 0 blades (i.e. just source panels)
• Improved VTK reading and writting

Impacted areas of the software
AeroDyn / OLAF

Supporting information

• Basic induced velocity calculation placed in FVW_BiotSavart.f90
• Main source panel routines placed in FVW_Subs with the suffix: srcPnl_
• All data stored into type T_SrcPanl* similar to T_Sgmt and T_Part.

Test results, if applicable
A unittest is included as part of FVW_Tests to check that the Cp of a sphere match the analytical value.

• Input file documentation, live version here
• r-test of the potential flow about a sphere, see here
• Acknowledge sponsor Accelerate Wind in source code, and potential banner when Src Panel used.

[jjonkman]

Review of the new input file documentation only.

[hkross]

@ebranlard Has the sphere unit test been added already, or is that still to be completed?

[ebranlard]

@ebranlard Has the sphere unit test been added already, or is that still to be completed?

The r-test for the potential flow about a sphere is now added, see here

[andrew-platt]

One of the regression tests is failing due to an incomplete preceding test (restart case). This is unrelated to the changes here.

[jjonkman]

Thanks for addressing my comments and updating the acknowledgements!

[ebranlard]

Thank you for the fast turnaround!