def build_structure(rigid_body_configs):
# Free joint represents the rigid-body motion of the platform
free_joint = FreeJoint('base')
for i, conf in enumerate(rigid_body_configs):
name = conf.get('name', 'body{}'.format(i))
conn = RigidConnection('conn-' + name, offset=conf['CoM'])
body = RigidBody(name,
mass=conf['mass'],
inertia=np.diag(conf['inertia']))
free_joint.add_leaf(conn)
conn.add_leaf(body)
system = System(free_joint)
return system
def __init__(self, structure_config):
s = structure_config
#### Load details of flexible elements ####
if "definition" in s["tower"]:
if "mass" in s["tower"]:
raise ValueError("Both tower definition and explicit mass!")
self.tower_definition = Tower(s["tower"]["definition"])
assert np.all(self.tower_definition.stn_pos[:, :2] == 0) # vert.
z_tower = self.tower_definition.stn_pos[:, 2]
self.tower_modes = ModesFromScratch(
z_tower - z_tower[0],
self.tower_definition.density,
1,
self.tower_definition.EIy,
self.tower_definition.EIz,
)
else:
self.tower_definition = None
self.tower_modes = None
if "blade" in s:
self.blade_modes = load_modes_from_Bladed(s["blade"]["definition"])
else:
self.blade_modes = None
#### Create the elements ####
# Free joint represents the rigid-body motion of the platform
free_joint = FreeJoint("base")
# This is the rigid-body mass of the platform structure
conn_platform = RigidConnection("conn-platform", offset=s["platform"]["CoM"])
platform = RigidBody("platform", mass=s["platform"]["mass"], inertia=np.diag(s["platform"]["inertia"]))
free_joint.add_leaf(conn_platform)
conn_platform.add_leaf(platform)
# Make a rigid body to represent the added mass
# (approximate to zero frequency)
# XXX this is skipping the coupling matrix
# A = whales_model.A(0)
# added_mass = RigidBody('added-mass', mass=np.diag(A[:3, :3]),
# inertia=A[3:, 3:])
# Flexible tower or equivalent rigid body
if self.tower_modes:
# move base of tower 10m up, and rotate so tower x-axis is vertical
conn_tower = RigidConnection("conn-tower", offset=[0, 0, z_tower[0]], rotation=rotmat_y(-pi / 2))
tower = DistalModalElementFromScratch("tower", self.tower_modes, s["tower"]["number of normal modes"])
else:
# move tower to COG
conn_tower = RigidConnection("conn-tower", offset=s["tower"]["CoM"])
tower = RigidBody("tower", s["tower"]["mass"], np.diag(s["tower"]["inertia"]))
free_joint.add_leaf(conn_tower)
conn_tower.add_leaf(tower)
# The nacelle -- rigid body
# rotate back so nacelle inertia is aligned with global coordinates
if self.tower_modes:
nacoff = s["nacelle"]["offset from tower top"]
conn_nacelle = RigidConnection(
"conn-nacelle", offset=dot(rotmat_y(pi / 2), nacoff), rotation=rotmat_y(pi / 2)
)
tower.add_leaf(conn_nacelle)
else:
conn_nacelle = RigidConnection("conn-nacelle", offset=np.array([0, 0, s["nacelle"]["height"]]))
free_joint.add_leaf(conn_nacelle)
nacelle = RigidBody(
"nacelle", mass=s["nacelle"]["mass"], inertia=np.diag(s["nacelle"].get("inertia", np.zeros(3)))
)
conn_nacelle.add_leaf(nacelle)
# The rotor hub -- currently just connections (no mass)
# rotate so rotor centre is aligned with global coordinates
if self.tower_modes:
rotoff = s["rotor"]["offset from tower top"]
conn_rotor = RigidConnection("conn-rotor", offset=dot(rotmat_y(pi / 2), rotoff), rotation=rotmat_y(pi / 2))
tower.add_leaf(conn_rotor)
else:
conn_rotor = RigidConnection("conn-rotor", offset=np.array([0, 0, s["nacelle"]["height"]]))
free_joint.add_leaf(conn_rotor)
# The drive shaft rotation (rotation about x)
shaft = Hinge("shaft", [1, 0, 0])
conn_rotor.add_leaf(shaft)
# The blades
if self.blade_modes:
rtlen = s["rotor"]["root length"]
Ryx = dot(rotmat_y(-pi / 2), rotmat_x(-pi / 2)) # align blade modes
for i in range(3):
R = rotmat_x(i * 2 * pi / 3)
root = RigidConnection("root%d" % (i + 1), offset=dot(R, [0, 0, rtlen]), rotation=dot(R, Ryx))
blade = ModalElement("blade%d" % (i + 1), self.blade_modes)
shaft.add_leaf(root)
root.add_leaf(blade)
else:
rotor = RigidBody("rotor", s["rotor"]["mass"], np.diag(s["rotor"]["inertia"]))
shaft.add_leaf(rotor)
# Build system
self.system = System(free_joint)
# Constrain missing DOFs -- tower torsion & extension not complete
if self.tower_modes:
self.system.prescribe(tower, vel=0, part=[0, 3])
class FloatingTurbineStructure(object):
def __init__(self, structure_config):
s = structure_config
#### Load details of flexible elements ####
if "definition" in s["tower"]:
if "mass" in s["tower"]:
raise ValueError("Both tower definition and explicit mass!")
self.tower_definition = Tower(s["tower"]["definition"])
assert np.all(self.tower_definition.stn_pos[:, :2] == 0) # vert.
z_tower = self.tower_definition.stn_pos[:, 2]
self.tower_modes = ModesFromScratch(
z_tower - z_tower[0],
self.tower_definition.density,
1,
self.tower_definition.EIy,
self.tower_definition.EIz,
)
else:
self.tower_definition = None
self.tower_modes = None
if "blade" in s:
self.blade_modes = load_modes_from_Bladed(s["blade"]["definition"])
else:
self.blade_modes = None
#### Create the elements ####
# Free joint represents the rigid-body motion of the platform
free_joint = FreeJoint("base")
# This is the rigid-body mass of the platform structure
conn_platform = RigidConnection("conn-platform", offset=s["platform"]["CoM"])
platform = RigidBody("platform", mass=s["platform"]["mass"], inertia=np.diag(s["platform"]["inertia"]))
free_joint.add_leaf(conn_platform)
conn_platform.add_leaf(platform)
# Make a rigid body to represent the added mass
# (approximate to zero frequency)
# XXX this is skipping the coupling matrix
# A = whales_model.A(0)
# added_mass = RigidBody('added-mass', mass=np.diag(A[:3, :3]),
# inertia=A[3:, 3:])
# Flexible tower or equivalent rigid body
if self.tower_modes:
# move base of tower 10m up, and rotate so tower x-axis is vertical
conn_tower = RigidConnection("conn-tower", offset=[0, 0, z_tower[0]], rotation=rotmat_y(-pi / 2))
tower = DistalModalElementFromScratch("tower", self.tower_modes, s["tower"]["number of normal modes"])
else:
# move tower to COG
conn_tower = RigidConnection("conn-tower", offset=s["tower"]["CoM"])
tower = RigidBody("tower", s["tower"]["mass"], np.diag(s["tower"]["inertia"]))
free_joint.add_leaf(conn_tower)
conn_tower.add_leaf(tower)
# The nacelle -- rigid body
# rotate back so nacelle inertia is aligned with global coordinates
if self.tower_modes:
nacoff = s["nacelle"]["offset from tower top"]
conn_nacelle = RigidConnection(
"conn-nacelle", offset=dot(rotmat_y(pi / 2), nacoff), rotation=rotmat_y(pi / 2)
)
tower.add_leaf(conn_nacelle)
else:
conn_nacelle = RigidConnection("conn-nacelle", offset=np.array([0, 0, s["nacelle"]["height"]]))
free_joint.add_leaf(conn_nacelle)
nacelle = RigidBody(
"nacelle", mass=s["nacelle"]["mass"], inertia=np.diag(s["nacelle"].get("inertia", np.zeros(3)))
)
conn_nacelle.add_leaf(nacelle)
# The rotor hub -- currently just connections (no mass)
# rotate so rotor centre is aligned with global coordinates
if self.tower_modes:
rotoff = s["rotor"]["offset from tower top"]
conn_rotor = RigidConnection("conn-rotor", offset=dot(rotmat_y(pi / 2), rotoff), rotation=rotmat_y(pi / 2))
tower.add_leaf(conn_rotor)
else:
conn_rotor = RigidConnection("conn-rotor", offset=np.array([0, 0, s["nacelle"]["height"]]))
free_joint.add_leaf(conn_rotor)
# The drive shaft rotation (rotation about x)
shaft = Hinge("shaft", [1, 0, 0])
conn_rotor.add_leaf(shaft)
# The blades
if self.blade_modes:
rtlen = s["rotor"]["root length"]
Ryx = dot(rotmat_y(-pi / 2), rotmat_x(-pi / 2)) # align blade modes
for i in range(3):
R = rotmat_x(i * 2 * pi / 3)
root = RigidConnection("root%d" % (i + 1), offset=dot(R, [0, 0, rtlen]), rotation=dot(R, Ryx))
blade = ModalElement("blade%d" % (i + 1), self.blade_modes)
shaft.add_leaf(root)
root.add_leaf(blade)
else:
rotor = RigidBody("rotor", s["rotor"]["mass"], np.diag(s["rotor"]["inertia"]))
shaft.add_leaf(rotor)
# Build system
self.system = System(free_joint)
# Constrain missing DOFs -- tower torsion & extension not complete
if self.tower_modes:
self.system.prescribe(tower, vel=0, part=[0, 3])
def set_rigid(self, what):
if what in ("tower", "all"):
self.system.prescribe(self.system.elements["tower"], vel=0)
if what in ("rotor", "all"):
for i in range(3):
self.system.prescribe(self.system.elements["blade%d" % (i + 1)], vel=0)
def set_flexible(self, what):
if what in ("tower", "all"):
self.system.free(self.system.elements["tower"])
# Constrain missing DOFs -- tower torsion & extension not complete
self.system.prescribe(self.system.elements["tower"], vel=0, part=[0, 3])
if what in ("rotor", "all"):
for i in range(3):
self.system.free(self.system.elements["blade%d" % (i + 1)])
def set_shaft_lock(self, locked):
if locked:
self.system.prescribe(self.system.elements["shaft"], vel=0)
else:
self.system.free(self.system.elements["shaft"])
def linearised_system(self, z0=None, zd0=None, mbc=False, perturbation=None):
# Linearise the system about the given operating point
self.system.update_kinematics()
linsys = LinearisedSystem.from_system(self.system, z0=z0, zd0=zd0, perturbation=perturbation)
# Apply multi-blade coordinate transform if needed
if mbc:
iazimuth = self.system.free_dof_indices("shaft")[0]
iblades = [self.system.free_dof_indices("blade{}".format(i + 1)) for i in range(3)]
if mbc == 2:
linsys = linsys.multiblade_transform2(iazimuth, iblades)
else:
linsys = linsys.multiblade_transform(iazimuth, iblades)
return linsys
def linearised_matrices(self, *args, **kwargs):
linsys = self.linearised_system(*args, **kwargs)
return linsys.M, linsys.C, linsys.K
def describe_states(self):
q = self.system.q
states = [(q.owners[j], i) for i, j in enumerate(q.dofs.subset)]
for owner, owner_states in itertools.groupby(states, lambda x: x[0]):
numbers = [x[1] for x in owner_states]
print "{:2}-{:2}: {}".format(numbers[0], numbers[-1], owner)
def __init__(self, structure_config):
s = structure_config
#### Load details of flexible elements ####
if 'definition' in s['tower']:
if 'mass' in s['tower']:
raise ValueError("Both tower definition and explicit mass!")
self.tower_definition = Tower(s['tower']['definition'])
assert np.all(self.tower_definition.stn_pos[:, :2] == 0) # vert.
z_tower = self.tower_definition.stn_pos[:, 2]
self.tower_modes = ModesFromScratch(
z_tower - z_tower[0],
self.tower_definition.density, 1,
self.tower_definition.EIy, self.tower_definition.EIz)
else:
self.tower_definition = None
self.tower_modes = None
if 'blade' in s:
self.blade_modes = load_modes_from_Bladed(s['blade']['definition'])
else:
self.blade_modes = None
#### Create the elements ####
# Free joint represents the rigid-body motion of the platform
free_joint = FreeJoint('base')
# This is the rigid-body mass of the platform structure
conn_platform = RigidConnection('conn-platform',
offset=s['platform']['CoM'])
platform = RigidBody('platform',
mass=s['platform']['mass'],
inertia=np.diag(s['platform']['inertia']))
free_joint.add_leaf(conn_platform)
conn_platform.add_leaf(platform)
# Make a rigid body to represent the added mass
# (approximate to zero frequency)
# XXX this is skipping the coupling matrix
#A = whales_model.A(0)
# added_mass = RigidBody('added-mass', mass=np.diag(A[:3, :3]),
# inertia=A[3:, 3:])
# Flexible tower or equivalent rigid body
if self.tower_modes:
# move base of tower 10m up, and rotate so tower x-axis is vertical
conn_tower = RigidConnection(
'conn-tower', offset=[0, 0, z_tower[0]],
rotation=rotmat_y(-pi/2))
tower = DistalModalElementFromScratch(
'tower', self.tower_modes,
s['tower']['number of normal modes'])
else:
# move tower to COG
conn_tower = RigidConnection(
'conn-tower', offset=s['tower']['CoM'])
tower = RigidBody('tower', s['tower']['mass'],
np.diag(s['tower']['inertia']))
free_joint.add_leaf(conn_tower)
conn_tower.add_leaf(tower)
# The nacelle -- rigid body
# rotate back so nacelle inertia is aligned with global coordinates
if self.tower_modes:
nacoff = s['nacelle']['offset from tower top']
conn_nacelle = RigidConnection('conn-nacelle',
offset=dot(rotmat_y(pi/2), nacoff),
rotation=rotmat_y(pi/2))
tower.add_leaf(conn_nacelle)
else:
conn_nacelle = RigidConnection(
'conn-nacelle',
offset=np.array([0, 0, s['nacelle']['height']]))
free_joint.add_leaf(conn_nacelle)
nacelle = RigidBody(
'nacelle',
mass=s['nacelle']['mass'],
inertia=np.diag(s['nacelle'].get('inertia', np.zeros(3))))
conn_nacelle.add_leaf(nacelle)
# The rotor hub -- currently just connections (no mass)
# rotate so rotor centre is aligned with global coordinates
if self.tower_modes:
rotoff = s['rotor']['offset from tower top']
conn_rotor = RigidConnection('conn-rotor',
offset=dot(rotmat_y(pi/2), rotoff),
rotation=rotmat_y(pi/2))
tower.add_leaf(conn_rotor)
else:
conn_rotor = RigidConnection(
'conn-rotor',
offset=np.array([0, 0, s['nacelle']['height']]))
free_joint.add_leaf(conn_rotor)
# The drive shaft rotation (rotation about x)
shaft = Hinge('shaft', [1, 0, 0])
conn_rotor.add_leaf(shaft)
# The blades
if self.blade_modes:
rtlen = s['rotor']['root length']
Ryx = dot(rotmat_y(-pi/2), rotmat_x(-pi/2)) # align blade modes
for i in range(3):
R = rotmat_x(i*2*pi/3)
root = RigidConnection('root%d' % (i+1),
offset=dot(R, [0, 0, rtlen]),
rotation=dot(R, Ryx))
blade = ModalElement('blade%d' % (i+1), self.blade_modes)
shaft.add_leaf(root)
root.add_leaf(blade)
else:
rotor = RigidBody('rotor', s['rotor']['mass'],
np.diag(s['rotor']['inertia']))
shaft.add_leaf(rotor)
# Build system
self.system = System(free_joint)
# Constrain missing DOFs -- tower torsion & extension not complete
if self.tower_modes:
self.system.prescribe(tower, vel=0, part=[0, 3])
class FloatingTurbineStructure(object):
def __init__(self, structure_config):
s = structure_config
#### Load details of flexible elements ####
if 'definition' in s['tower']:
if 'mass' in s['tower']:
raise ValueError("Both tower definition and explicit mass!")
self.tower_definition = Tower(s['tower']['definition'])
assert np.all(self.tower_definition.stn_pos[:, :2] == 0) # vert.
z_tower = self.tower_definition.stn_pos[:, 2]
self.tower_modes = ModesFromScratch(
z_tower - z_tower[0],
self.tower_definition.density, 1,
self.tower_definition.EIy, self.tower_definition.EIz)
else:
self.tower_definition = None
self.tower_modes = None
if 'blade' in s:
self.blade_modes = load_modes_from_Bladed(s['blade']['definition'])
else:
self.blade_modes = None
#### Create the elements ####
# Free joint represents the rigid-body motion of the platform
free_joint = FreeJoint('base')
# This is the rigid-body mass of the platform structure
conn_platform = RigidConnection('conn-platform',
offset=s['platform']['CoM'])
platform = RigidBody('platform',
mass=s['platform']['mass'],
inertia=np.diag(s['platform']['inertia']))
free_joint.add_leaf(conn_platform)
conn_platform.add_leaf(platform)
# Make a rigid body to represent the added mass
# (approximate to zero frequency)
# XXX this is skipping the coupling matrix
#A = whales_model.A(0)
# added_mass = RigidBody('added-mass', mass=np.diag(A[:3, :3]),
# inertia=A[3:, 3:])
# Flexible tower or equivalent rigid body
if self.tower_modes:
# move base of tower 10m up, and rotate so tower x-axis is vertical
conn_tower = RigidConnection(
'conn-tower', offset=[0, 0, z_tower[0]],
rotation=rotmat_y(-pi/2))
tower = DistalModalElementFromScratch(
'tower', self.tower_modes,
s['tower']['number of normal modes'])
else:
# move tower to COG
conn_tower = RigidConnection(
'conn-tower', offset=s['tower']['CoM'])
tower = RigidBody('tower', s['tower']['mass'],
np.diag(s['tower']['inertia']))
free_joint.add_leaf(conn_tower)
conn_tower.add_leaf(tower)
# The nacelle -- rigid body
# rotate back so nacelle inertia is aligned with global coordinates
if self.tower_modes:
nacoff = s['nacelle']['offset from tower top']
conn_nacelle = RigidConnection('conn-nacelle',
offset=dot(rotmat_y(pi/2), nacoff),
rotation=rotmat_y(pi/2))
tower.add_leaf(conn_nacelle)
else:
conn_nacelle = RigidConnection(
'conn-nacelle',
offset=np.array([0, 0, s['nacelle']['height']]))
free_joint.add_leaf(conn_nacelle)
nacelle = RigidBody(
'nacelle',
mass=s['nacelle']['mass'],
inertia=np.diag(s['nacelle'].get('inertia', np.zeros(3))))
conn_nacelle.add_leaf(nacelle)
# The rotor hub -- currently just connections (no mass)
# rotate so rotor centre is aligned with global coordinates
if self.tower_modes:
rotoff = s['rotor']['offset from tower top']
conn_rotor = RigidConnection('conn-rotor',
offset=dot(rotmat_y(pi/2), rotoff),
rotation=rotmat_y(pi/2))
tower.add_leaf(conn_rotor)
else:
conn_rotor = RigidConnection(
'conn-rotor',
offset=np.array([0, 0, s['nacelle']['height']]))
free_joint.add_leaf(conn_rotor)
# The drive shaft rotation (rotation about x)
shaft = Hinge('shaft', [1, 0, 0])
conn_rotor.add_leaf(shaft)
# The blades
if self.blade_modes:
rtlen = s['rotor']['root length']
Ryx = dot(rotmat_y(-pi/2), rotmat_x(-pi/2)) # align blade modes
for i in range(3):
R = rotmat_x(i*2*pi/3)
root = RigidConnection('root%d' % (i+1),
offset=dot(R, [0, 0, rtlen]),
rotation=dot(R, Ryx))
blade = ModalElement('blade%d' % (i+1), self.blade_modes)
shaft.add_leaf(root)
root.add_leaf(blade)
else:
rotor = RigidBody('rotor', s['rotor']['mass'],
np.diag(s['rotor']['inertia']))
shaft.add_leaf(rotor)
# Build system
self.system = System(free_joint)
# Constrain missing DOFs -- tower torsion & extension not complete
if self.tower_modes:
self.system.prescribe(tower, vel=0, part=[0, 3])
def set_rigid(self, what):
if what in ('tower', 'all'):
self.system.prescribe(self.system.elements['tower'], vel=0)
if what in ('rotor', 'all'):
for i in range(3):
self.system.prescribe(self.system.elements['blade%d' % (i+1)],
vel=0)
def set_flexible(self, what):
if what in ('tower', 'all'):
self.system.free(self.system.elements['tower'])
# Constrain missing DOFs -- tower torsion & extension not complete
self.system.prescribe(self.system.elements['tower'], vel=0,
part=[0, 3])
if what in ('rotor', 'all'):
for i in range(3):
self.system.free(self.system.elements['blade%d' % (i+1)])
def set_shaft_lock(self, locked):
if locked:
self.system.prescribe(self.system.elements['shaft'], vel=0)
else:
self.system.free(self.system.elements['shaft'])
def linearised_system(self, z0=None, zd0=None, mbc=False,
perturbation=None):
# Linearise the system about the given operating point
self.system.update_kinematics()
linsys = LinearisedSystem.from_system(self.system, z0=z0, zd0=zd0,
perturbation=perturbation)
# Apply multi-blade coordinate transform if needed
if mbc:
iazimuth = self.system.free_dof_indices('shaft')[0]
iblades = [self.system.free_dof_indices('blade{}'.format(i+1))
for i in range(3)]
if mbc == 2:
linsys = linsys.multiblade_transform2(iazimuth, iblades)
else:
linsys = linsys.multiblade_transform(iazimuth, iblades)
return linsys
def linearised_matrices(self, *args, **kwargs):
linsys = self.linearised_system(*args, **kwargs)
return linsys.M, linsys.C, linsys.K
def describe_states(self):
q = self.system.q
states = [(q.owners[j], i) for i, j in enumerate(q.dofs.subset)]
for owner, owner_states in itertools.groupby(states, lambda x: x[0]):
numbers = [x[1] for x in owner_states]
print '{:2}-{:2}: {}'.format(numbers[0], numbers[-1], owner)
