def rotor_example1(n_el=48):
"""
This function instantiate a rotor similar to the example 5.9.1, page 206 (Dynamics of rotating machine, FRISSWELL)
The following functions test_example1_w_equals0rpm() and test_example1_w_equals4000rpm() are the test functions of
this example.
P.S.:Isotropic bearings.
:param w: speed of rotation.
:param n_el: number of shaft elements.
:return: Rotor object.
"""
shaft_elm = []
for i in range(n_el):
shaft_elm.append(
rs.ShaftElement(L=1.5 / n_el, material=steel, n=i, i_d=0,
o_d=0.05))
disk0 = rs.DiskElement.from_geometry(n=(n_el / 1.5) * 0.5,
material=steel,
width=0.07,
i_d=0.05,
o_d=0.28)
disk1 = rs.DiskElement.from_geometry(n=(n_el / 1.5),
material=steel,
width=0.07,
i_d=0.05,
o_d=0.35)
bearing0 = rs.BearingElement(n=0, kxx=1e6, kyy=1e6, cxx=0, cyy=0)
bearing1 = rs.BearingElement(n=n_el, kxx=1e6, kyy=1e6, cxx=0, cyy=0)
return rs.Rotor(shaft_elm, [disk0, disk1], [bearing0, bearing1])
def rotor_example2(n_el=48):
"""
This function instantiate a overhung rotor similar to the example 5.9.9, page 218 (Dynamics of rotating machine,
FRISSWELL).
The following functions test_example2_w_equals0rpm() and test_example2_w_equals4000rpm() are the test functions of
this example.
P.S.: Overhung rotor.
:param n_el: number of shaft elements.
:return: Rotor object.
"""
shaft_elm = []
for i in range(n_el):
shaft_elm.append(
rs.ShaftElement(L=1.5 / n_el, material=steel, n=i, i_d=0,
o_d=0.05))
return rs.Rotor(
shaft_elm,
[
rs.DiskElement.from_geometry(
n=n_el, material=steel, width=0.07, i_d=0.05, o_d=0.35)
],
[
rs.BearingElement(n=0, kxx=10e6, kyy=10e6, cxx=0, cyy=0),
rs.BearingElement(
n=int((n_el / 1.5)), kxx=10e6, kyy=10e6, cxx=0, cyy=0),
],
)
def rotor_example7(w=0, n_el=48):
"""
This function instantiate a rotor similar to the example 5.9.10, page 219 (Dynamics of rotating machine, FRISSWELL)
The following functions test_example7_w_equals0rpm() and test_example7_w_equals4000rpm() are the test functions of
this example.
P.S.: Tapered shaft and damped bearings with anisotropic properties.
:param w: speed of rotation.
:param n_el: number of shaft elements.
:return: Rotor object.
"""
shaft_elm = []
for i in range(n_el):
shaft_elm.append(
rs.ShaftElement(L=1.5 / n_el,
material=steel,
n=i,
i_d=0,
o_d=0.025 + 0.015 * (i / n_el)))
disk0 = rs.DiskElement.from_geometry(n=(n_el / 2),
material=steel,
width=0.07,
i_d=0.05,
o_d=0.28)
bearing0 = rs.BearingElement(n=0, kxx=1e7, kyy=1e7, cxx=1e3, cyy=1e3)
bearing1 = rs.BearingElement(n=n_el, kxx=1e7, kyy=1e7, cxx=1e3, cyy=1e3)
return rs.Rotor(shaft_elm, [disk0], [bearing0, bearing1], w=w)
def base_rotor_example():
"""Internal routine that create an example of a rotor, to be used in
the associated crack problems as a prerequisite.
This function returns an instance of a 6 DoF rotor, with a number of
components attached. As this is not the focus of the example here, but
only a requisite, see the example in "rotor assembly" for additional
information on the rotor object.
Returns
-------
rotor : ross.Rotor Object
An instance of a flexible 6 DoF rotor object.
Examples
--------
>>> rotor = base_rotor_example()
>>> rotor.Ip
0.015118294226367068
"""
steel2 = ross.Material(name="Steel", rho=7850, E=2.17e11, G_s=81.2e9)
# Rotor with 6 DoFs, with internal damping, with 10 shaft elements, 2 disks and 2 bearings.
i_d = 0
o_d = 0.019
n = 33
# fmt: off
L = np.array(
[0 , 25, 64, 104, 124, 143, 175, 207, 239, 271,
303, 335, 345, 355, 380, 408, 436, 466, 496, 526,
556, 586, 614, 647, 657, 667, 702, 737, 772, 807,
842, 862, 881, 914]
)/ 1000
# fmt: on
L = [L[i] - L[i - 1] for i in range(1, len(L))]
shaft_elem = [
ross.ShaftElement6DoF(
material=steel2,
L=l,
idl=i_d,
odl=o_d,
idr=i_d,
odr=o_d,
alpha=8.0501,
beta=1.0e-5,
rotary_inertia=True,
shear_effects=True,
)
for l in L
]
Id = 0.003844540885417
Ip = 0.007513248437500
disk0 = ross.DiskElement6DoF(n=12, m=2.6375, Id=Id, Ip=Ip)
disk1 = ross.DiskElement6DoF(n=24, m=2.6375, Id=Id, Ip=Ip)
kxx1 = 4.40e5
kyy1 = 4.6114e5
kzz = 0
cxx1 = 27.4
cyy1 = 2.505
czz = 0
kxx2 = 9.50e5
kyy2 = 1.09e8
cxx2 = 50.4
cyy2 = 100.4553
bearing0 = ross.BearingElement6DoF(
n=4, kxx=kxx1, kyy=kyy1, cxx=cxx1, cyy=cyy1, kzz=kzz, czz=czz
)
bearing1 = ross.BearingElement6DoF(
n=31, kxx=kxx2, kyy=kyy2, cxx=cxx2, cyy=cyy2, kzz=kzz, czz=czz
)
rotor = ross.Rotor(shaft_elem, [disk0, disk1], [bearing0, bearing1])
return rotor
bearing0 = rs.BearingElement6DoF(n=4,
kxx=kxx1,
kyy=kyy1,
cxx=cxx1,
cyy=cyy1,
kzz=kzz,
czz=czz)
bearing1 = rs.BearingElement6DoF(n=31,
kxx=kxx2,
kyy=kyy2,
cxx=cxx2,
cyy=cyy2,
kzz=kzz,
czz=czz)
rotor = rs.Rotor(shaft_elem, [disk0, disk1], [bearing0, bearing1])
@pytest.fixture
def rub():
unbalance_magnitudet = np.array([5e-4, 0])
unbalance_phaset = np.array([-np.pi / 2, 0])
rubbing = rotor.run_rubbing(
dt=0.001,
tI=0,
tF=0.5,
deltaRUB=7.95e-5,
kRUB=1.1e6,
cRUB=40,
n_balls = 7
d_balls = 0.006
fs = 10
alpha = (np.pi / 18)
bearings = [
rs.BallBearingElement(
n=i*2,
n_balls=n_balls,
d_balls=d_balls,
fs=fs,
alpha=alpha,
tag=(f"Rolamento de esferas {i}")
)
for i in range(N_bearing)
]
# ===========================================
# ROTOR
#
rotor = rs.Rotor(shaft_elements, [disk_geo], bearings)
rotor.plot_rotor()
# ===========================================
# DIAGRAMA DE CAMPBELL
#
samples = 50
speed_range = np.linspace(20, 1000, samples) # [rad/s]
campbell = rotor.run_campbell(speed_range)
campbell.plot()
