Include MAP++ file

[nikhar-abbas]

Include MAP++ file

This pull request is to include a MAP++ input file for the IEA15MW UMaineSemi mooring system model. The primary motivation for this is so that we can linearize the FOWT model with HydroDyn and the platform's translational DOFs of the platform enabled. This necessitates a mooring-line model, and the most recent release of OpenFAST (v2.4) does not support linearization with MoorDyn.

Inputs

All relevant input parameters for the MAP++ input file were copied from the existing MoorDyn input file. Notably the parameters: CB, CIntDamp, Ca, Cdn, and Cdt are unimportant.

MoorDyn Comparisons

I ran some free-decay testing to ensure that the MAP++ mooring line model behaves as expected. The MAP++ model is compared to the existing MoorDyn model in the results from these tests that are linked below. To give some context, the simulation parameters were as follows:

• OpenFAST 2.4 was run, compiled in double precision using intel compilers.
• 150 second simulations were run
• All OpenFAST modules were turned off, except:

  CompElast = 1
  CompHydro = 1
  CompMooring = 1/3

  This means that there was no inflow wind condition

• Only Ptfm* ElastoDyn DOFs were enabled, so the rotor is not spinning.
• WaveMod = 0 (still water) in HydroDyn

For each simulation, a single platform DOF was significantly perturbed, while the rest were left at 0. All floating DOFs were enabled to get a better idea of the coupling effects that might be happening. Presumably, a similar test for only one DOF enabled would be useful as well, but I am confident enough in the attached results that I don't think this is necessary.

Results: freedecay_heave.pdf freedecay_pitch.pdf freedecay_roll.pdf freedecay_surge.pdf freedecay_sway.pdf freedecay_yaw.pdf

[gbarter]

Thank you for such a complete PR with documentation and analysis!