def geometry_description(self):
"""This function calculates the geometry description.
It is executed when the class is instantiated.
Examples
--------
>>> my_fluid_flow = fluid_flow_example()
>>> my_fluid_flow.geometry_description()
"""
if self.shape_geometry == "cylindrical":
start = (np.pi / 2) + self.attitude_angle
else:
start = 0
for i in range(0, self.nz):
zno = i * self.dz
self.z_list[i] = zno
for j in range(0, self.ntheta):
# fmt: off
self.gama[i, j] = j * self.dtheta + start
[radius_external, self.xre[i, j], self.yre[i, j]] = \
external_radius_function(self.gama[i, j], self.radius_stator, self.radius_rotor,
shape=self.shape_geometry, preload=self.preload,
displacement=self.displacement, max_depth=self.max_depth)
[radius_internal, self.xri[i, j], self.yri[i, j]] = \
internal_radius_function(self.gama[i, j], self.attitude_angle, self.radius_rotor,
self.eccentricity)
self.re[i, j] = radius_external
self.ri[i, j] = radius_internal
def geometry_description(self):
"""This function calculates the geometry description.
It is executed when the class is instantiated.
Examples
--------
>>> my_fluid_flow = fluid_flow_example()
>>> my_fluid_flow.geometry_description()
"""
for i in range(0, self.nz):
zno = i * self.dz
self.z_list[i] = zno
for j in range(0, self.ntheta):
# fmt: off
self.gama[i, j] = j * self.dtheta + np.pi / 2 + self.attitude_angle
[radius_external, self.xre[i, j], self.yre[i, j]] = \
external_radius_function(self.gama[i, j], self.radius_stator)
[radius_internal, self.xri[i, j], self.yri[i, j]] = \
internal_radius_function(self.gama[i, j], self.attitude_angle, self.radius_rotor,
self.eccentricity)
self.re[i, j] = radius_external
self.ri[i, j] = radius_internal
def calculate_coefficients(self, direction=None):
"""This function calculates the constants that form the Poisson equation
of the discrete pressure (central differences in the second
derivatives). It is executed when the class is instantiated.
Examples
--------
>>> my_fluid_flow = fluid_flow_example()
>>> my_fluid_flow.calculate_coefficients()
>>> my_fluid_flow.c0w # doctest: +ELLIPSIS
array([[...
"""
for i in range(0, self.nz):
zno = i * self.dz
self.z_list[i] = zno
eccentricity_error = False
for j in range(0, self.ntheta):
# fmt: off
self.gama[i][j] = j * self.dtheta + np.pi / 2 + self.attitude_angle
[radius_external, self.xre[i][j], self.yre[i][j]] = \
external_radius_function(self.gama[i][j], self.radius_stator)
[radius_internal, self.xri[i][j], self.yri[i][j]] = \
internal_radius_function(self.gama[i][j], self.attitude_angle, self.radius_rotor,
self.eccentricity)
self.re[i][j] = radius_external
self.ri[i][j] = radius_internal
w = self.omega * self.radius_rotor
k = (self.re[i][j] ** 2 * (np.log(self.re[i][j]) - 1 / 2) - self.ri[i][j] ** 2 *
(np.log(self.ri[i][j]) - 1 / 2)) / (self.ri[i][j] ** 2 - self.re[i][j] ** 2)
self.c1[i][j] = (1 / (4 * self.viscosity)) * ((self.re[i][j] ** 2 * np.log(self.re[i][j]) -
self.ri[i][j] ** 2 * np.log(self.ri[i][j]) +
(self.re[i][j] ** 2 - self.ri[i][j] ** 2) *
(k - 1)) - 2 * self.re[i][j] ** 2 * (
(np.log(self.re[i][j]) + k - 1 / 2) * np.log(
self.re[i][j] / self.ri[i][j])))
self.c2[i][j] = (- self.ri[i][j] ** 2) / (8 * self.viscosity) * \
((self.re[i][j] ** 2 - self.ri[i][j] ** 2 -
(self.re[i][j] ** 4 - self.ri[i][j] ** 4) /
(2 * self.ri[i][j] ** 2)) +
((self.re[i][j] ** 2 - self.ri[i][j] ** 2) /
(self.ri[i][j] ** 2 *
np.log(self.re[i][j] / self.ri[i][j]))) *
(self.re[i][j] ** 2 * np.log(self.re[i][j] / self.ri[i][j]) -
(self.re[i][j] ** 2 - self.ri[i][j] ** 2) / 2))
self.c0w[i][j] = (- w * self.ri[i][j] *
(np.log(self.re[i][j] / self.ri[i][j]) *
(1 + (self.ri[i][j] ** 2) / (self.re[i][j] ** 2 - self.ri[i][j] ** 2)) - 1 / 2))
if direction == "x":
a = self.omegap * (self.xp) * np.cos(self.omegap * self.t)
self.c0w[i][j] += self.ri[i][j] * a * np.sin(self.gama[i][j])
elif direction == "y":
b = self.omegap * (self.yp) * np.cos(self.omegap * self.t)
self.c0w[i][j] -= self.ri[i][j] * b * np.cos(self.gama[i][j])
else:
self.c0w[i][j] += 0
# fmt: on
if not eccentricity_error:
if abs(self.xri[i][j]) > abs(self.xre[i][j]) or abs(
self.yri[i][j]
) > abs(self.yre[i][j]):
eccentricity_error = True
if eccentricity_error:
raise ValueError(
"Error: The given parameters create a rotor that is not inside the stator. "
"Check parameters and fix accordingly."
)
