Feature: Add wind speed dependency in heterogeneous inflows

[Bartdoekemeijer]

Expand heterogeneous inflows to allow different speed-ups per ambient wind speed

This feature allows users to specify a different speed-up factor for each ambient wind speed in the heterogeneous inflow functionality.

Related issue

There is no dedicated issue, but the problem is nicely highlighted in this post: #578 (comment).

Impacted areas of the software

FLORIS core simulation.

Additional supporting information

This change is API breaking, because it forces the heterogeneous inflow definition to match the shape (n_wind_directions, n_wind_speeds, n_hetmap_coordinates).

Test results, if applicable

Here is a piece of code where I compare nominal solutions at 10.0 and 9.0 m/s with the heterogeneous inflow solutions where I use a freestream inflow of 5.0 and 6.0 m/s, respectively, with speed-up factors of 2.0 and 1.5. These two solutions in theory should be equal.

import numpy as np

from floris.tools import FlorisInterface
from floris.tools.visualization import visualize_cut_plane

# Initialize FLORIS with the given input file via FlorisInterface.
# Note the heterogeneous inflow is defined in the input file.
fi = FlorisInterface("inputs/gch_heterogeneous_inflow.yaml")

# Calculate nominal solutions without speed-ups
heterogenous_inflow_config = {
    'speed_multipliers': [[[1.0, 1.0, 1.0, 1.0]]],
    'x': [-5000.0, -5000.0, 5000.0, 5000.0],
    'y': [ -5000.0, 5000.0, -5000.0, 5000.0],
}
fi.reinitialize(wind_shear=0.0, layout_x=[-299, 299], layout_y=[0., 0.], heterogenous_inflow_config=heterogenous_inflow_config)

fi.reinitialize(wind_speeds=[10.0], wind_directions=[270.],)
fi.calculate_wake()
turbine_powers_10ms_270deg = fi.get_turbine_powers().flatten() / 1000.

fi.reinitialize(wind_speeds=[9.0], wind_directions=[275.],)
fi.calculate_wake()
turbine_powers_9ms_275deg = fi.get_turbine_powers().flatten() / 1000.

# Now calculate solutions with heterogeneous inflows
speed_multipliers = [
    [
        [2.0, 2.0, 2.0, 2.0],  # Wind direction 270, Wind speed 5.0, four locations (x,y)
        [1.5, 1.5, 1.5, 1.5],  # Wind direction 270, Wind speed 6.0, four locations (x,y)
    ],
    [
        [2.0, 2.0, 2.0, 2.0],  # Wind direction 275, Wind speed 5.0, four locations (x,y)
        [1.5, 1.5, 1.5, 1.5],  # Wind direction 275, Wind speed 6.0, four locations (x,y)
    ],
]
heterogenous_inflow_config["speed_multipliers"]= speed_multipliers
fi.reinitialize(
    wind_directions=[270.0, 275.0],
    wind_speeds=[5.0, 6.0],
    heterogenous_inflow_config=heterogenous_inflow_config
)
fi.calculate_wake()
turbine_powers = fi.get_turbine_powers() / 1000.
turbine_powers_5ms_270deg_hetmultiplier2 = turbine_powers[0, 0, :].flatten()
turbine_powers_6ms_275deg_hetmultiplier15 = turbine_powers[1, 1, :].flatten()

# Now cross-compare
print("Evaluation with 270 deg, 10 m/s:")
print(f"  Nominal: {turbine_powers_10ms_270deg}")
print(f"  5 m/s with heterogeneous multiplier of 2.0: {turbine_powers_5ms_270deg_hetmultiplier2}")

print("Evaluation with 275 deg, 9.0 m/s:")
print(f"  Nominal: {turbine_powers_9ms_275deg}")
print(f"  6.0 m/s with heterogeneous multiplier of 1.5: {turbine_powers_6ms_275deg_hetmultiplier15}")

And they are equal:

Evaluation with 270 deg, 10 m/s:
  Nominal: [3329.10062735  368.38870676]
  5 m/s with heterogeneous multiplier of 2.0: [3329.10062735  368.38870676]
Evaluation with 275 deg, 9.0 m/s:
  Nominal: [2430.57780918  986.0126126 ]
  6.0 m/s with heterogeneous multiplier of 1.5: [2430.57780918  986.0126126 ]

[misi9170]

Hi @Bartdoekemeijer , I think this is now addressed in Floris v4. The heterogeneous_inflow_config can simply be set for every findex, but we now also have capability for specifying heterogeneity by wd and ws bin in the WindRose format, which was introduced in #902.