Wake-added turbulence in FAST.Farm

[ebranlard]

This pull request is ready to be merged

Feature or improvement description Implementation of the wake-added turbulence into FAST.Farm

Impacted areas of the software FAST.Farm

Additional supporting information The feature and input file changes has been documented, but it requires the calibration of its two main constants. r-tests and additional documentation will follow after the calibration.

The following additional inputs are added to the input file:

--- WAKE-ADDED TURBULENCE ---
0                  WAT                - Switch between wake-added turbulence box options {0: no wake added turbulence, 1: predefined turbulence box, 2: user defined turbulence box} (switch)
"Inflow/WAT/isoturb_1024x32x16.u" WAT_BoxFile  - Filepath to the file containing the u-component of the turbulence box (either predefined or user-defined) (quoted string)
1024, 32, 16       WAT_NxNyNz         - Number of points in the x, y, and z directions of the WAT_BoxFile [used only if WAT=2, derived value if WAT=1] (-)
5.5, 4.0, 4.0      WAT_DxDyDz         - Distance (in meters) between points in the x, y, and z directions of the WAT_BoxFile [used only if WAT=2, derived value if WAT=1] (m)
default            WAT_ScaleBox       - Flag to scale the input turbulence box to zero mean and unit standard deviation at every node [DEFAULT=False] (flag)
0.5                WAT_k_Def          - Calibrated parameter for the influence of the wake deficit in the wake-added turbulence [>=0.0, no upper bound] or DEFAULT [DEFAULT=NONE]
0.5                WAT_k_Grad         - Calibrated parameter for the influence of the radial velocity gradient of the wake deficit in the wake-added turbulence [>=0.0, no upper bound] or DEFAULT [DEFAULT=NONE]
default            WAT_D_BrkDwn       - Downstream distance in rotor diameter after which WAT scaling has reached 100% capacity [>=0] or DEFAULT [DEFAULT=1] (D)

Test results, if applicable Test results are unchanged.

• [ ] Implement the downstream evolution of kdef and kgrad using eddy viscosity function and 4 input parameters

[andrew-platt]

Temporary links to readthedocs changes for proofing: https://ap-openfast.readthedocs.io/en/f-ffwat/source/user/fast.farm/InputFiles.html#wake-added-turbulence-wat https://ap-openfast.readthedocs.io/en/f-ffwat/source/user/fast.farm/FFarmTheory.html#wake-added-turbulence-wat

[andrew-platt]

For finalizing:

• [ ] implement the k_def and k_grad functions from paper (@ebranlard)
• [ ] Merge in dev-unstable-pointers to resolve conflicts
• [ ] Update all FF test cases to include WAT by default, then regen results
• [ ] User documentation (link to paper for now -- maybe pull in pieces from paper)

[andrew-platt]

This PR is replaced by https://github.com/OpenFAST/openfast/pull/2202