floris.core.wake_turbulence.crespo_hernandez

Classes

CrespoHernandez([initial, constant, ai, ...])

CrespoHernandez is a wake-turbulence model that is used to compute additional variability introduced to the flow field by operation of a wind turbine.

class floris.core.wake_turbulence.crespo_hernandez.CrespoHernandez(initial=0.1, constant=0.9, ai=0.8, downstream=-0.32)

CrespoHernandez is a wake-turbulence model that is used to compute additional variability introduced to the flow field by operation of a wind turbine. Implementation of the model follows the original formulation and limitations outlined in [1].

Args:

parameter_dictionary (dict): Model-specific parameters.

Default values are used when a parameter is not included in parameter_dictionary. Possible key-value pairs include:

• initial (float): The initial ambient turbulence intensity, expressed as a decimal fraction.

• constant (float): The constant used to scale the wake-added turbulence intensity.

• ai (float): The axial induction factor exponent used in in the calculation of wake-added turbulence.

• downstream (float): The exponent applied to the distance downstream of an upstream turbine normalized by the rotor diameter used in the calculation of wake-added turbulence.

References:

[1] (1,2,3)

A Crespo and J Hernandez. Turbulence characteristics in wind-turbine wakes. Journal of wind engineering and industrial aerodynamics, 61(1):71–85, 1996.

Parameters:

• initial (float)

• constant (float)

• ai (float)

• downstream (float)

initial: float

constant: float

ai: float

downstream: float

prepare_function()

Return type:

dict

function(ambient_TI, x, x_i, rotor_diameter, axial_induction)

Return type:

None

Parameters:

• ambient_TI (float)

• x (ndarray)

• x_i (ndarray)

• rotor_diameter (float)

• axial_induction (ndarray)