diff --git a/linerate/equations/cigre207/__init__.py b/linerate/equations/cigre207/__init__.py
index af02088..d2c20ed 100644
--- a/linerate/equations/cigre207/__init__.py
+++ b/linerate/equations/cigre207/__init__.py
@@ -2,4 +2,4 @@
 This submodule contains implementations of equations listed in :cite:p:`cigre207`.
 """
 
-from . import convective_cooling, solar_heating  # noqa
\ No newline at end of file
+from . import convective_cooling, solar_heating  # noqa
diff --git a/linerate/equations/cigre207/ac_resistance.py b/linerate/equations/cigre207/ac_resistance.py
index 748baef..550128f 100644
--- a/linerate/equations/cigre207/ac_resistance.py
+++ b/linerate/equations/cigre207/ac_resistance.py
@@ -1,5 +1,3 @@
-from typing import Union
-
 from linerate.units import OhmPerMeter
 
 
@@ -24,4 +22,4 @@ def correct_resistance_for_skin_effect(
     return 1.0123 * dc_resistance
 
 
-# TODO: Implement section 2.1.2?
\ No newline at end of file
+# TODO: Implement section 2.1.2?
diff --git a/linerate/equations/cigre207/convective_cooling.py b/linerate/equations/cigre207/convective_cooling.py
index 8a0be0a..3a727d4 100644
--- a/linerate/equations/cigre207/convective_cooling.py
+++ b/linerate/equations/cigre207/convective_cooling.py
@@ -9,11 +9,11 @@
     Meter,
     MeterPerSecond,
     Radian,
+    SquareMeterPerSecond,
     Unitless,
-    WattPerMeterPerKelvin, SquareMeterPerSecond,
+    WattPerMeterPerKelvin,
 )
 
-
 # Physical quantities
 #####################
 
@@ -40,10 +40,9 @@ def compute_thermal_conductivity_of_air(film_temperature: Celsius) -> WattPerMet
     return 2.42e-2 + 7.2e-5 * T_f
 
 
-def compute_relative_air_density(
-    height_above_sea_level: Meter
-) -> Unitless:
-    r"""Approximation of the relative density of air at a given altitude, relative to density at sea level.
+def compute_relative_air_density(height_above_sea_level: Meter) -> Unitless:
+    r"""Approximation of the relative density of air at a given altitude,
+    relative to density at sea level.
 
     Equation on page 6 of :cite:p:`cigre207`.
 
@@ -58,7 +57,7 @@ def compute_relative_air_density(
         :math:`\rho_r`. The relative mass density of air.
     """
     y = height_above_sea_level
-    return np.exp(-1.16e-4*y)
+    return np.exp(-1.16e-4 * y)
 
 
 def compute_kinematic_viscosity_of_air(film_temperature: Celsius) -> KilogramPerCubeMeter:
@@ -79,8 +78,7 @@ def compute_kinematic_viscosity_of_air(film_temperature: Celsius) -> KilogramPer
         :math:`\nu_f~\left[\text{m}^2~\text{s}^{-1}\right]`. The kinematic viscosity of air.
     """
     T_f = film_temperature
-    return 1.32e-5 + 9.5e-8*T_f
-
+    return 1.32e-5 + 9.5e-8 * T_f
 
 
 def compute_prandtl_number(
@@ -104,14 +102,14 @@ def compute_prandtl_number(
     Union[float, float64, ndarray[Any, dtype[float64]]]
         :math:`\text{Pr}`. The Prandtl number.
     """
-    return 0.715 - 2.5e-4*film_temperature
+    return 0.715 - 2.5e-4 * film_temperature
 
 
 def compute_reynolds_number(
     wind_speed: MeterPerSecond,
     conductor_diameter: Meter,
     kinematic_viscosity_of_air: SquareMeterPerSecond,
-    relative_air_density: Unitless
+    relative_air_density: Unitless,
 ) -> Unitless:
     r"""Compute the Reynolds number using the conductor diameter as characteristic length scale.
 
@@ -142,7 +140,6 @@ def compute_reynolds_number(
     return rho_r * v * D / nu_f
 
 
-
 ## Nusselt number calculation
 #############################
 
@@ -219,8 +216,7 @@ def compute_low_wind_speed_nusseltnumber(
     Union[float, float64, ndarray[Any, dtype[float64]]]
         :math:`\text{Nu}_{90}`. The corrected Nusselt number for low wind speed.
     """
-    return 0.55*perpendicular_flow_nusselt_number
-
+    return 0.55 * perpendicular_flow_nusselt_number
 
 
 @vectorize(nopython=True)
@@ -265,8 +261,7 @@ def correct_wind_direction_effect_on_nusselt_number(
         :math:`\text{Nu}_\delta`. The Nusselt number for the given wind angle-of-attack.
     """
     return _correct_wind_direction_effect_on_nusselt_number(
-        perpendicular_flow_nusselt_number,
-        angle_of_attack
+        perpendicular_flow_nusselt_number, angle_of_attack
     )
 
 
@@ -337,7 +332,7 @@ def compute_nusselt_number(
     forced_convection_nusselt_number: Unitless,
     natural_nusselt_number: Unitless,
     low_wind_nusselt_number: Unitless,
-    wind_speed: MeterPerSecond
+    wind_speed: MeterPerSecond,
 ) -> Unitless:
     r"""Compute the nusselt number.
 
diff --git a/linerate/equations/cigre207/solar_heating.py b/linerate/equations/cigre207/solar_heating.py
index df756fa..ef6b4d0 100644
--- a/linerate/equations/cigre207/solar_heating.py
+++ b/linerate/equations/cigre207/solar_heating.py
@@ -1,8 +1,8 @@
 import numpy as np
 from numpy import pi
 
-from .. import cigre601
 from ...units import Meter, Unitless, WattPerSquareMeter
+from .. import cigre601
 
 
 def compute_direct_solar_radiation(
@@ -19,8 +19,8 @@ def compute_direct_solar_radiation(
         N_s \frac{1280 \sin(H_s)}{\sin(H_s) + 0.314},
 
     where :math:`H_s` is the solar altitude.
-    To correct for height above sea level, we use the Eq. 19 from Cigre 601, since no equation is provided
-    in Cigre 207.
+    To correct for height above sea level, we use the Eq. 19 from Cigre 601,
+    since no equation is provided in Cigre 207.
 
     Parameters
     ----------
@@ -35,7 +35,9 @@ def compute_direct_solar_radiation(
         :math:`I_B~\left[\text{W}~\text{m}^{-2}\right]`. The direct solar radiation.
     """
     clearness_ratio = 1.0
-    return cigre601.solar_heating.compute_direct_solar_radiation(sin_solar_altitude, clearness_ratio, height_above_sea_level)
+    return cigre601.solar_heating.compute_direct_solar_radiation(
+        sin_solar_altitude, clearness_ratio, height_above_sea_level
+    )
 
 
 def compute_diffuse_sky_radiation(
@@ -64,7 +66,7 @@ def compute_diffuse_sky_radiation(
     """
     sin_H_s = sin_solar_altitude
     I_B = direct_solar_radiation
-    return np.maximum(0, (570 - 0.47 * I_B)) * np.maximum(0, sin_H_s)**1.2
+    return np.maximum(0, (570 - 0.47 * I_B)) * np.maximum(0, sin_H_s) ** 1.2
 
 
 def compute_global_radiation_intensity(
@@ -142,4 +144,4 @@ def compute_global_radiation_intensity(
     sin_eta = sin_angle_of_sun_on_line
     F_pi_half = 0.5 * pi * F
 
-    return I_B * (sin_eta + F_pi_half * sin_H_s) + I_d * pi/2 * (1 + F)  # type: ignore
+    return I_B * (sin_eta + F_pi_half * sin_H_s) + I_d * pi / 2 * (1 + F)  # type: ignore
diff --git a/linerate/equations/cigre601/convective_cooling.py b/linerate/equations/cigre601/convective_cooling.py
index c02ff29..2069062 100644
--- a/linerate/equations/cigre601/convective_cooling.py
+++ b/linerate/equations/cigre601/convective_cooling.py
@@ -15,16 +15,15 @@
     WattPerMeterPerKelvin,
 )
 
-
 # Physical quantities
 #####################
 
 
 def compute_temperature_gradient(
-        total_heat_gain: WattPerMeter,
-        conductor_thermal_conductivity: WattPerMeterPerKelvin,
-        core_diameter: Meter,
-        conductor_diameter: Meter,
+    total_heat_gain: WattPerMeter,
+    conductor_thermal_conductivity: WattPerMeterPerKelvin,
+    core_diameter: Meter,
+    conductor_diameter: Meter,
 ) -> Celsius:
     r"""Compute the difference between the core and surface temperature.
 
@@ -64,8 +63,8 @@ def compute_temperature_gradient(
     if D_1 == 0:  # TODO: Maybe lower tolerance?
         return 0.5 * tmp
     else:
-        D_1_sq = D_1 ** 2
-        delta_D_sq = D ** 2 - D_1_sq
+        D_1_sq = D_1**2
+        delta_D_sq = D**2 - D_1_sq
         return tmp * (0.5 - (D_1_sq / delta_D_sq) * np.log(D / D_1))
 
 
@@ -90,11 +89,11 @@ def compute_thermal_conductivity_of_air(film_temperature: Celsius) -> WattPerMet
         conductivity of air at the given temperature.
     """
     T_f = film_temperature
-    return 2.368e-2 + 7.23e-5 * T_f - 2.763e-8 * (T_f ** 2)
+    return 2.368e-2 + 7.23e-5 * T_f - 2.763e-8 * (T_f**2)
 
 
 def compute_air_density(
-        film_temperature: Celsius, height_above_sea_level: Meter
+    film_temperature: Celsius, height_above_sea_level: Meter
 ) -> KilogramPerCubeMeter:
     r"""Approximation of the density of air at a given temperature and altitude.
 
@@ -116,7 +115,7 @@ def compute_air_density(
     """
     T_f = film_temperature
     y = height_above_sea_level
-    return (1.293 - 1.525e-4 * y + 6.379e-9 * (y ** 2)) / (1 + 0.00367 * T_f)
+    return (1.293 - 1.525e-4 * y + 6.379e-9 * (y**2)) / (1 + 0.00367 * T_f)
 
 
 def compute_dynamic_viscosity_of_air(film_temperature: Celsius) -> KilogramPerMeterPerSecond:
@@ -138,11 +137,11 @@ def compute_dynamic_viscosity_of_air(film_temperature: Celsius) -> KilogramPerMe
         of air.
     """
     T_f = film_temperature
-    return 17.239e-6 + 4.635e-8 * T_f - 2.03e-11 * (T_f ** 2)
+    return 17.239e-6 + 4.635e-8 * T_f - 2.03e-11 * (T_f**2)
 
 
 def compute_kinematic_viscosity_of_air(
-        dynamic_viscosity_of_air: KilogramPerMeterPerSecond, air_density: KilogramPerCubeMeter
+    dynamic_viscosity_of_air: KilogramPerMeterPerSecond, air_density: KilogramPerCubeMeter
 ) -> SquareMeterPerSecond:
     r"""Compute the kinematic viscosity of air.
 
@@ -185,8 +184,8 @@ def _check_perpendicular_flow_nusseltnumber_out_of_bounds(reynolds_number, condu
 
 @vectorize(nopython=True)
 def _compute_perpendicular_flow_nusseltnumber(
-        reynolds_number: Unitless,
-        conductor_roughness: Meter,
+    reynolds_number: Unitless,
+    conductor_roughness: Meter,
 ) -> Unitless:
     # TODO: Look at references for this table
     Re = reynolds_number
@@ -216,12 +215,12 @@ def _compute_perpendicular_flow_nusseltnumber(
         else:
             B, n = 0.048, 0.800
 
-    return B * Re ** n  # type: ignore
+    return B * Re**n  # type: ignore
 
 
 def compute_perpendicular_flow_nusseltnumber(
-        reynolds_number: Unitless,
-        conductor_roughness: Meter,
+    reynolds_number: Unitless,
+    conductor_roughness: Meter,
 ) -> Unitless:
     r"""Compute the Nusselt number for perpendicular flow.
 
@@ -253,9 +252,9 @@ def compute_perpendicular_flow_nusseltnumber(
 
 @vectorize(nopython=True)
 def _correct_wind_direction_effect_on_nusselt_number(
-        perpendicular_flow_nusselt_number: Unitless,
-        angle_of_attack: Radian,
-        conductor_roughness: Unitless,
+    perpendicular_flow_nusselt_number: Unitless,
+    angle_of_attack: Radian,
+    conductor_roughness: Unitless,
 ) -> Unitless:
     delta = angle_of_attack
     Nu_90 = perpendicular_flow_nusselt_number
@@ -264,23 +263,23 @@ def _correct_wind_direction_effect_on_nusselt_number(
     sin_delta = np.sin(delta)
 
     if Rs == 0 or np.isnan(Rs):
-        sin_delta_sq = sin_delta ** 2
+        sin_delta_sq = sin_delta**2
         cos_delta_sq = 1 - sin_delta_sq
 
         correction_factor = (sin_delta_sq + cos_delta_sq * 0.0169) ** 0.225
     else:
         if delta <= np.radians(24):
-            correction_factor = 0.42 + 0.68 * (sin_delta ** 1.08)
+            correction_factor = 0.42 + 0.68 * (sin_delta**1.08)
         else:
-            correction_factor = 0.42 + 0.58 * (sin_delta ** 0.90)
+            correction_factor = 0.42 + 0.58 * (sin_delta**0.90)
 
     return correction_factor * Nu_90
 
 
 def correct_wind_direction_effect_on_nusselt_number(
-        perpendicular_flow_nusselt_number: Unitless,
-        angle_of_attack: Radian,
-        conductor_roughness: Unitless,
+    perpendicular_flow_nusselt_number: Unitless,
+    angle_of_attack: Radian,
+    conductor_roughness: Unitless,
 ) -> Unitless:
     r"""Correct the Nusselt number for the wind's angle-of-attack.
 
@@ -315,7 +314,7 @@ def correct_wind_direction_effect_on_nusselt_number(
 
 
 def _check_horizontal_natural_nusselt_number(
-        grashof_number: Unitless, prandtl_number: Unitless
+    grashof_number: Unitless, prandtl_number: Unitless
 ) -> None:
     GrPr = grashof_number * prandtl_number
     if np.any(GrPr < 0):
@@ -326,26 +325,26 @@ def _check_horizontal_natural_nusselt_number(
 
 @vectorize(nopython=True)
 def _compute_horizontal_natural_nusselt_number(
-        grashof_number: Unitless,
-        prandtl_number: Unitless,
+    grashof_number: Unitless,
+    prandtl_number: Unitless,
 ) -> Unitless:
     GrPr = grashof_number * prandtl_number
 
     if GrPr < 1e-1:
         return 0
     elif GrPr < 1e2:
-        return 1.020 * GrPr ** 0.148
+        return 1.020 * GrPr**0.148
     elif GrPr < 1e4:
-        return 0.850 * GrPr ** 0.188
+        return 0.850 * GrPr**0.188
     elif GrPr < 1e7:
-        return 0.480 * GrPr ** 0.250
+        return 0.480 * GrPr**0.250
     else:
-        return 0.125 * GrPr ** 0.333
+        return 0.125 * GrPr**0.333
 
 
 def compute_horizontal_natural_nusselt_number(
-        grashof_number: Unitless,
-        prandtl_number: Unitless,
+    grashof_number: Unitless,
+    prandtl_number: Unitless,
 ) -> Unitless:
     r"""The Nusselt number for natural (passive) convection on a horizontal conductor.
 
@@ -378,8 +377,8 @@ def compute_horizontal_natural_nusselt_number(
 
 
 def _check_conductor_inclination(
-        conductor_inclination: Radian,
-        conductor_roughness: Unitless,
+    conductor_inclination: Radian,
+    conductor_roughness: Unitless,
 ) -> None:
     beta = np.degrees(conductor_inclination)
     Rs = conductor_roughness
@@ -396,24 +395,24 @@ def _check_conductor_inclination(
 
 @vectorize(nopython=True)
 def _correct_natural_nusselt_number_inclination(
-        horizontal_natural_nusselt_number: Unitless,
-        conductor_inclination: Radian,
-        conductor_roughness: Unitless,
+    horizontal_natural_nusselt_number: Unitless,
+    conductor_inclination: Radian,
+    conductor_roughness: Unitless,
 ) -> Unitless:
     beta = np.degrees(conductor_inclination)
     Nu_nat = horizontal_natural_nusselt_number
     Rs = conductor_roughness
 
     if Rs == 0 or np.isnan(Rs):
-        return Nu_nat * (1 - 1.58e-4 * beta ** 1.5)
+        return Nu_nat * (1 - 1.58e-4 * beta**1.5)
     else:
-        return Nu_nat * (1 - 1.76e-6 * beta ** 2.5)
+        return Nu_nat * (1 - 1.76e-6 * beta**2.5)
 
 
 def correct_natural_nusselt_number_inclination(
-        horizontal_natural_nusselt_number: Unitless,
-        conductor_inclination: Radian,
-        conductor_roughness: Unitless,
+    horizontal_natural_nusselt_number: Unitless,
+    conductor_inclination: Radian,
+    conductor_roughness: Unitless,
 ) -> Unitless:
     r"""Correct the natural Nusselt number for the effect of the span inclination.
 
@@ -447,8 +446,8 @@ def correct_natural_nusselt_number_inclination(
 
 
 def compute_nusselt_number(
-        forced_convection_nusselt_number: Unitless,
-        natural_nusselt_number: Unitless,
+    forced_convection_nusselt_number: Unitless,
+    natural_nusselt_number: Unitless,
 ) -> Unitless:
     r"""Compute the nusselt number.
 
diff --git a/linerate/equations/cigre601/solar_heating.py b/linerate/equations/cigre601/solar_heating.py
index 575920f..aef33c8 100644
--- a/linerate/equations/cigre601/solar_heating.py
+++ b/linerate/equations/cigre601/solar_heating.py
@@ -1,7 +1,7 @@
 import numpy as np
 from numpy import pi
 
-from ...units import Meter, Unitless, WattPerMeter, WattPerSquareMeter
+from ...units import Meter, Unitless, WattPerSquareMeter
 
 
 def compute_direct_solar_radiation(
diff --git a/linerate/equations/convective_cooling.py b/linerate/equations/convective_cooling.py
index cec9a54..2c7b427 100644
--- a/linerate/equations/convective_cooling.py
+++ b/linerate/equations/convective_cooling.py
@@ -1,17 +1,18 @@
 import numpy as np
 
-from linerate.units import Celsius, Unitless, WattPerMeterPerKelvin, WattPerMeter
+from linerate.units import Celsius, Unitless, WattPerMeter, WattPerMeterPerKelvin
 
 
 def compute_convective_cooling(
-        surface_temperature: Celsius,
-        air_temperature: Celsius,
-        nusselt_number: Unitless,
-        thermal_conductivity_of_air: WattPerMeterPerKelvin,
+    surface_temperature: Celsius,
+    air_temperature: Celsius,
+    nusselt_number: Unitless,
+    thermal_conductivity_of_air: WattPerMeterPerKelvin,
 ) -> WattPerMeter:
     r"""Compute the convective cooling of the conductor.
 
-    Equation (17) on page 24 of :cite:p:`cigre601` and Equation (12) on page 6 of :cite:p:`cigre207`.
+    Equation (17) on page 24 of :cite:p:`cigre601`
+    and Equation (12) on page 6 of :cite:p:`cigre207`.
 
     Parameters
     ----------
@@ -37,4 +38,4 @@ def compute_convective_cooling(
     T_a = air_temperature
     Nu = nusselt_number
 
-    return pi * lambda_f * (T_s - T_a) * Nu
\ No newline at end of file
+    return pi * lambda_f * (T_s - T_a) * Nu
diff --git a/linerate/equations/dimensionless.py b/linerate/equations/dimensionless.py
index 10430ad..a1e7c3e 100644
--- a/linerate/equations/dimensionless.py
+++ b/linerate/equations/dimensionless.py
@@ -2,8 +2,17 @@
 
 import numpy as np
 
-from linerate.units import Unitless, WattPerMeterPerKelvin, KilogramPerMeterPerSecond, JoulePerKilogramPerKelvin, \
-    MeterPerSecond, Meter, SquareMeterPerSecond, Celsius, MeterPerSquareSecond
+from linerate.units import (
+    Celsius,
+    JoulePerKilogramPerKelvin,
+    KilogramPerMeterPerSecond,
+    Meter,
+    MeterPerSecond,
+    MeterPerSquareSecond,
+    SquareMeterPerSecond,
+    Unitless,
+    WattPerMeterPerKelvin,
+)
 
 
 def compute_reynolds_number(
@@ -13,7 +22,8 @@ def compute_reynolds_number(
 ) -> Unitless:
     r"""Compute the Reynolds number using the conductor diameter as characteristic length scale.
 
-    Defined in the text on page 25 of :cite:p:`cigre601` and equation (2c) on page 10 in :cite:p:`ieee738`.
+    Defined in the text on page 25 of :cite:p:`cigre601` and equation (2c)
+    on page 10 in :cite:p:`ieee738`.
 
     The Reynolds number is a dimensionless quantity that can be used to assess if a stream is
     likely to be turbulent or not. It is given by
@@ -125,8 +135,8 @@ def compute_prandtl_number(
 
 
 def compute_conductor_roughness(
-        conductor_diameter: Meter,
-        outer_layer_strand_diameter: Meter,
+    conductor_diameter: Meter,
+    outer_layer_strand_diameter: Meter,
 ) -> Unitless:
     r"""Compute the surface roughness of the conductor.
 
diff --git a/linerate/equations/solar_heating.py b/linerate/equations/solar_heating.py
index 0cfe465..a177116 100644
--- a/linerate/equations/solar_heating.py
+++ b/linerate/equations/solar_heating.py
@@ -1,4 +1,4 @@
-from linerate.units import WattPerSquareMeter, Unitless, Meter, WattPerMeter
+from linerate.units import Meter, Unitless, WattPerMeter, WattPerSquareMeter
 
 
 def compute_solar_heating(
diff --git a/linerate/model.py b/linerate/model.py
index 2a4ad26..cad6982 100644
--- a/linerate/model.py
+++ b/linerate/model.py
@@ -11,15 +11,19 @@
 from typing import Dict
 
 import numpy as np
+from models.cigre207 import Cigre207
 
 from linerate import solver
 from linerate.equations import (
     cigre601,
+    convective_cooling,
+    dimensionless,
     ieee738,
     joule_heating,
     math,
     radiative_cooling,
-    solar_angles, convective_cooling, dimensionless, solar_heating,
+    solar_angles,
+    solar_heating,
 )
 from linerate.equations.math import switch_cos_sin
 from linerate.types import Span, Weather
@@ -32,7 +36,7 @@
     WattPerMeter,
 )
 
-__all__ = ["ThermalModel", "Cigre601", "IEEE738"]
+__all__ = ["ThermalModel", "Cigre601", "IEEE738", "Cigre207"]
 
 
 def _copy_method_docstring(parent_class):
diff --git a/linerate/models/Cigre207.md b/linerate/models/Cigre207.md
index 62c190a..ad23e73 100644
--- a/linerate/models/Cigre207.md
+++ b/linerate/models/Cigre207.md
@@ -33,4 +33,4 @@ viscosity $\nu_f$ has to be corrected for the air relative density.
 
 Cigre 207 has a non-smooth transition to low wind speeds (<0.5m/s) at angles of attack less than 45 degrees.
 This leads to an increase in cooling as the wind speed drops below 0.5m/s, which seems non-physical.
-This discontinuity is removed in Cigre 601.
\ No newline at end of file
+This discontinuity is removed in Cigre 601.
diff --git a/linerate/models/cigre207.py b/linerate/models/cigre207.py
index 5343364..96277f2 100644
--- a/linerate/models/cigre207.py
+++ b/linerate/models/cigre207.py
@@ -1,11 +1,19 @@
 from abc import abstractmethod
 
-from linerate import ThermalModel, Span, Weather
-from linerate.equations import solar_angles, cigre601, math, cigre207, dimensionless, convective_cooling, joule_heating, \
-    solar_heating
+from linerate import Span, ThermalModel, Weather
+from linerate.equations import (
+    cigre207,
+    cigre601,
+    convective_cooling,
+    dimensionless,
+    joule_heating,
+    math,
+    solar_angles,
+    solar_heating,
+)
 from linerate.equations.math import switch_cos_sin
 from linerate.model import _copy_method_docstring
-from linerate.units import Date, Celsius, Ampere, WattPerMeter, OhmPerMeter
+from linerate.units import Ampere, Celsius, Date, OhmPerMeter, WattPerMeter
 
 
 class Cigre207(ThermalModel):
@@ -80,9 +88,6 @@ def compute_convective_cooling(
         )
 
         # Compute unitless quantities
-        # Reynolds number is defined in the text on page 5 of :cite:p:`cigre207`.
-        # The definition includes a relative air density, which does not make sense, so we omit it here and use the
-        # standard definition of Reynolds number instead.
         rho_r = cigre207.convective_cooling.compute_relative_air_density(y)
         Re = cigre207.convective_cooling.compute_reynolds_number(V, D, nu_f, rho_r)
         Gr = dimensionless.compute_grashof_number(D, T_c, T_a, nu_f)
@@ -101,8 +106,10 @@ def compute_convective_cooling(
         Nu_0 = cigre207.convective_cooling.compute_horizontal_natural_nusselt_number(Gr, Pr)
 
         Nu = cigre207.convective_cooling.compute_nusselt_number(
-            forced_convection_nusselt_number=Nu_delta, natural_nusselt_number=Nu_0,
-            low_wind_nusselt_number=Nu_cor, wind_speed=V
+            forced_convection_nusselt_number=Nu_delta,
+            natural_nusselt_number=Nu_0,
+            low_wind_nusselt_number=Nu_cor,
+            wind_speed=V,
         )
 
         return convective_cooling.compute_convective_cooling(
diff --git a/tests/equations/cigre207/test_convective_cooling.py b/tests/equations/cigre207/test_convective_cooling.py
index e6b0a7f..44695fb 100644
--- a/tests/equations/cigre207/test_convective_cooling.py
+++ b/tests/equations/cigre207/test_convective_cooling.py
@@ -1,6 +1,7 @@
 import numpy as np
 from pytest import approx
-from linerate.equations import cigre207, dimensionless, convective_cooling
+
+from linerate.equations import cigre207, dimensionless
 
 
 def test_matches_example1():
@@ -10,7 +11,7 @@ def test_matches_example1():
     assert rho_r == approx(0.8306, rel=1e-4)
     T_s = 57
     T_amb = 40
-    T_f = (T_s + T_amb)/2
+    T_f = (T_s + T_amb) / 2
     nu_f = cigre207.convective_cooling.compute_kinematic_viscosity_of_air(T_f)
     assert nu_f == approx(1.78e-5, rel=1e-3)
     v = 2
@@ -29,7 +30,9 @@ def test_matches_example1_nusselt_number():
     Re = 2670
     Nu_90 = cigre207.convective_cooling.compute_perpendicular_flow_nusseltnumber(Re, Rs)
     assert Nu_90 == approx(26.45, 1e-4)
-    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(Nu_90, np.radians(45))
+    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(
+        Nu_90, np.radians(45)
+    )
     assert Nu_45 == approx(22.34, rel=1e-4)
 
 
@@ -41,7 +44,7 @@ def test_matches_example2():
     T_amb = 40
     v = 0.2
     D = 0.0286
-    T_f = (T_s + T_amb)/2
+    T_f = (T_s + T_amb) / 2
     nu_f = cigre207.convective_cooling.compute_kinematic_viscosity_of_air(T_f)
     nu_f_exp = 1.95e-5
     assert nu_f == approx(nu_f_exp, rel=1e-3)
@@ -53,7 +56,9 @@ def test_matches_example2():
     Rs = dimensionless.compute_conductor_roughness(D, d)
     Nu_90 = cigre207.convective_cooling.compute_perpendicular_flow_nusseltnumber(Re, Rs)
     assert Nu_90 == approx(8.53, 1e-3)
-    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(Nu_90, np.radians(45))
+    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(
+        Nu_90, np.radians(45)
+    )
     assert Nu_45 == approx(7.20, rel=2e-3)
     Nu_cor = cigre207.convective_cooling.compute_low_wind_speed_nusseltnumber(Nu_90)
     assert Nu_cor == approx(4.69, rel=1e-3)
@@ -76,7 +81,7 @@ def test_matches_example3():
     v = 2
     D = 0.0286
     d = 0.00318
-    T_f = (T_s + T_amb)/2
+    T_f = (T_s + T_amb) / 2
     nu_f = cigre207.convective_cooling.compute_kinematic_viscosity_of_air(T_f)
     nu_f_exp = 1.866e-5
     assert nu_f == approx(nu_f_exp, rel=1e-3)
@@ -87,7 +92,9 @@ def test_matches_example3():
     Rs = dimensionless.compute_conductor_roughness(D, d)
     Nu_90 = cigre207.convective_cooling.compute_perpendicular_flow_nusseltnumber(Re, Rs)
     assert Nu_90 == approx(25.77, 1e-3)
-    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(Nu_90, np.radians(45))
+    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(
+        Nu_90, np.radians(45)
+    )
     assert Nu_45 == approx(21.8, rel=2e-3)
 
 
@@ -99,7 +106,7 @@ def test_matches_example4():
     T_amb = 40
     v = 0.4
     D = 0.0286
-    T_f = (T_s + T_amb)/2
+    T_f = (T_s + T_amb) / 2
     nu_f = cigre207.convective_cooling.compute_kinematic_viscosity_of_air(T_f)
     nu_f_exp = 1.866e-5
     assert nu_f == approx(nu_f_exp, rel=1e-3)
@@ -111,7 +118,9 @@ def test_matches_example4():
     Rs = dimensionless.compute_conductor_roughness(D, d)
     Nu_90 = cigre207.convective_cooling.compute_perpendicular_flow_nusseltnumber(Re, Rs)
     assert Nu_90 == approx(12.08, 1e-3)
-    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(Nu_90, np.radians(45))
+    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(
+        Nu_90, np.radians(45)
+    )
     assert Nu_45 == approx(10.2, rel=2e-3)
     Nu_cor = cigre207.convective_cooling.compute_low_wind_speed_nusseltnumber(Nu_90)
     assert Nu_cor == approx(6.64, rel=1e-3)
@@ -134,7 +143,7 @@ def test_matches_example5():
     T_amb = 40
     v = 2
     D = 0.0286
-    T_f = (T_s + T_amb)/2
+    T_f = (T_s + T_amb) / 2
     nu_f = cigre207.convective_cooling.compute_kinematic_viscosity_of_air(T_f)
     nu_f_exp = 1.78e-5
     assert nu_f == approx(nu_f_exp, rel=1e-3)
@@ -146,5 +155,7 @@ def test_matches_example5():
     Rs = dimensionless.compute_conductor_roughness(D, d)
     Nu_90 = cigre207.convective_cooling.compute_perpendicular_flow_nusseltnumber(Re, Rs)
     assert Nu_90 == approx(29.85, 1e-3)
-    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(Nu_90, np.radians(45))
+    Nu_45 = cigre207.convective_cooling.correct_wind_direction_effect_on_nusselt_number(
+        Nu_90, np.radians(45)
+    )
     assert Nu_45 == approx(25.21, rel=2e-3)
diff --git a/tests/equations/cigre601/test_convective_cooling.py b/tests/equations/cigre601/test_convective_cooling.py
index 6e690c4..841f0f8 100644
--- a/tests/equations/cigre601/test_convective_cooling.py
+++ b/tests/equations/cigre601/test_convective_cooling.py
@@ -7,7 +7,6 @@
 
 import linerate.equations.cigre601.convective_cooling as convective_cooling
 
-
 # Tests for physical quantities
 ###############################
 
@@ -260,8 +259,6 @@ def test_kinematic_viscosity_of_air_with_example():
     assert convective_cooling.compute_kinematic_viscosity_of_air(mu_f, gamma) == approx(1)
 
 
-
-
 ## Nusselt number calculation
 #############################
 
diff --git a/tests/equations/test_convective_cooling.py b/tests/equations/test_convective_cooling.py
index f16f208..b0fc0dc 100644
--- a/tests/equations/test_convective_cooling.py
+++ b/tests/equations/test_convective_cooling.py
@@ -1,8 +1,8 @@
 import hypothesis
 import hypothesis.strategies as st
 import numpy as np
-
 from pytest import approx
+
 from linerate.equations import convective_cooling
 
 
@@ -130,4 +130,4 @@ def test_cooling_matches_cigre207_example4():
     T_amb = 40
     Nu_45 = 10.2
     cooling = convective_cooling.compute_convective_cooling(T_s, T_amb, Nu_45, 0.0283)
-    assert cooling == approx(31.78, rel=2e-3)
\ No newline at end of file
+    assert cooling == approx(31.78, rel=2e-3)
diff --git a/tests/equations/test_radiative_cooling.py b/tests/equations/test_radiative_cooling.py
index 6170138..27586bf 100644
--- a/tests/equations/test_radiative_cooling.py
+++ b/tests/equations/test_radiative_cooling.py
@@ -87,11 +87,7 @@ def test_radiative_cooling_with_example(
 
 @pytest.mark.parametrize(
     "surface_temperature, expected_cooling",
-    [
-        (57, 5.76),
-        (93, 21.27),
-        (75, 12.92)
-    ],
+    [(57, 5.76), (93, 21.27), (75, 12.92)],
 )
 def test_cooling_matches_cigre207_examples(surface_temperature, expected_cooling):
     # See Appendix 1, Example 1 in Cigre 207
@@ -99,4 +95,4 @@ def test_cooling_matches_cigre207_examples(surface_temperature, expected_cooling
     D = 0.0286
     epsilon = 0.5
     cooling = radiative_cooling.compute_radiative_cooling(surface_temperature, T_a, D, epsilon)
-    assert cooling == approx(expected_cooling, rel=2e-3)
\ No newline at end of file
+    assert cooling == approx(expected_cooling, rel=2e-3)