import numpy as np
from foxes.core import WakeSuperposition
import foxes.variables as FV
import foxes.constants as FC
[docs]
class WSProduct(WakeSuperposition):
"""
Product supersposition of wind deficit results
This is based on the idea that the dimensionless
wind deficit should be rescaled with the wake
corrected wind field, rather than the rotor
equivalent wind speed.
Source: https://arxiv.org/pdf/2010.03873.pdf
Equation (8)
Attributes
----------
lim_low: float
Lower limit of the final waked wind speed
lim_high: float
Upper limit of the final waked wind speed
:group: models.wake_superpositions
"""
[docs]
def __init__(self, lim_low=None, lim_high=None):
"""
Constructor.
Parameters
----------
lim_low: float
Lower limit of the final waked wind speed
lim_high: float
Upper limit of the final waked wind speed
"""
super().__init__()
self.lim_low = lim_low
self.lim_high = lim_high
[docs]
def __repr__(self):
a = f"lim_low={self.lim_low}, lim_high={self.lim_high}"
return f"{type(self).__name__}({a})"
[docs]
def add_wake(
self,
algo,
mdata,
fdata,
tdata,
downwind_index,
st_sel,
variable,
wake_delta,
wake_model_result,
):
"""
Add a wake delta to previous wake deltas,
at rotor points.
Parameters
----------
algo: foxes.core.Algorithm
The calculation algorithm
mdata: foxes.core.MData
The model data
fdata: foxes.core.FData
The farm data
tdata: foxes.core.TData
The target point data
downwind_index: int
The index of the wake causing turbine
in the downwnd order
st_sel: numpy.ndarray of bool
The selection of targets, shape: (n_states, n_targets)
variable: str
The variable name for which the wake deltas applies
wake_delta: numpy.ndarray
The original wake deltas, shape:
(n_states, n_targets, n_tpoints, ...)
wake_model_result: numpy.ndarray
The new wake deltas of the selected rotors,
shape: (n_st_sel, n_tpoints, ...)
Returns
-------
wdelta: numpy.ndarray
The updated wake deltas, shape:
(n_states, n_targets, n_tpoints, ...)
"""
if variable not in [FV.REWS, FV.REWS2, FV.REWS3, FV.WS]:
raise ValueError(
f"Superposition '{self.name}': Expecting wind speed variable, got {variable}"
)
if np.any(st_sel):
if np.max(np.abs(wake_delta)) < 1e-14:
wake_delta[:] = 1
wake_delta[st_sel] *= 1 + wake_model_result
return wake_delta
[docs]
def calc_final_wake_delta(
self,
algo,
mdata,
fdata,
variable,
amb_results,
wake_delta,
):
"""
Calculate the final wake delta after adding all
contributions.
Parameters
----------
algo: foxes.core.Algorithm
The calculation algorithm
mdata: foxes.core.MData
The model data
fdata: foxes.core.FData
The farm data
variable: str
The variable name for which the wake deltas applies
amb_results: numpy.ndarray
The ambient results at targets,
shape: (n_states, n_targets, n_tpoints)
wake_delta: numpy.ndarray
The wake deltas at targets, shape:
(n_states, n_targets, n_tpoints)
Returns
-------
final_wake_delta: numpy.ndarray
The final wake delta, which will be added to the ambient
results by simple plus operation. Shape:
(n_states, n_targets, n_tpoints)
"""
w = amb_results * (wake_delta - 1)
if self.lim_low is not None:
w = np.maximum(w, self.lim_low - amb_results)
if self.lim_high is not None:
w = np.minimum(w, self.lim_high - amb_results)
return w