def testSetterGetter(self):
g = np.array([0., 0., -9.81])
system = fsi.ProtChSystem()
system.setGravitationalAcceleration(g)
g0 = system.getGravitationalAcceleration()
npt.assert_almost_equal(g0, g)
mesh = fsi.ProtChMesh(system)
mesh.getChronoObject()
body = fsi.ProtChBody(system)
# position
pos = np.array([1., 2., 3.])
body.setPosition(pos)
pos0 = body.getPosition()
npt.assert_almost_equal(pos0, pos)
# inertia
inertia = np.array([[1., 4., 5.], [4., 2., 6.], [5., 6., 3.]])
inertiaXX = np.array([inertia[0, 0], inertia[1, 1], inertia[2, 2]])
inertiaXY = np.array([inertia[0, 1], inertia[0, 2], inertia[1, 2]])
body.setInertiaXX(inertiaXX)
# inertiaXX0 = body.getInertiaXX()
body.setInertiaXY(inertiaXY)
# inertiaXY0 = body.getInertiaXY()
inertia0 = body.getInertia()
# npt.assert_almost_equal(inertiaXX0, inertiaXX)
# npt.assert_almost_equal(inertiaXY0, inertiaXY)
npt.assert_almost_equal(inertia0, inertia)
# mass
mass = 10.2
body.setMass(mass)
mass0 = body.getMass()
npt.assert_almost_equal(mass0, mass)
def testHangingCableANCF(self):
g = np.array([0., 0., -9.81])
system = fsi.ProtChSystem()
system.ChSystem.Set_G_acc(chrono.ChVectorD(g[0], g[1], g[2]))
system.setTimeStep(1e-1)
# timestepper = chrono.ChTimestepperEulerImplicitLinearized()
# system.ChSystem.SetTimestepper(timestepper)
solver = chrono.ChSolverMINRES()
system.ChSystem.SetSolver(solver)
solver.SetMaxIterations(100)
solver.EnableWarmStart(True)
solver.EnableDiagonalPreconditioner(True)
solver.SetVerbose(True)
system.ChSystem.SetSolverForceTolerance(1e-10)
system.ChSystem.SetSolverMaxIterations(100)
mesh = fsi.ProtChMesh(system)
L = np.array([5.])
nb_elems = np.array([3])
d = np.array([1e-3])
rho = np.array([1000.])
E = np.array([1e10])
cable_type = b"CableANCF"
fairlead_body = fsi.ProtChBody(system)
fairlead_body.ChBody.SetBodyFixed(True)
mooring = fsi.ProtChMoorings(system=system,
mesh=mesh,
length=L,
nb_elems=nb_elems,
d=d,
rho=rho,
E=E,
beam_type=cable_type)
mooring.external_forces_manual = True # tri: should work without this line
# vertical cable
mooring.setNodesPositionFunction(lambda s: np.array([0., 0., s]),
lambda s: np.array([0., 0., 1.]))
mooring.setNodesPosition()
mooring.buildNodes()
mooring.attachBackNodeToBody(fairlead_body)
system.calculate_init()
system.calculate(0.5)
T = mooring.getTensionBack()
strain = mooring.getNodesTension(eta=1.)[-1] * np.pi * d**2 / 4 * E
T_sol = -np.ones(3) * g * rho * (np.pi * d**2 / 4. * L)
npt.assert_almost_equal(-T, T_sol)
floor=True)
cat1.computeSolution()
cat2.computeSolution()
# ANCHOR
# arbitrary body fixed in space
body2 = fsi.ProtChBody(system)
body2.barycenter0 = np.zeros(3)
# fix anchor in space
body2.ChBody.SetBodyFixed(True)
# MESH
# initialize mesh that will be used for cables
mesh = fsi.ProtChMesh(system)
# FEM CABLES
# moorings line 1
m1 = fsi.ProtChMoorings(system=system,
mesh=mesh,
length=np.array([L]),
nb_elems=np.array([nb_elems]),
d=np.array([d]),
rho=np.array([dens]),
E=np.array([E]))
m1.setName(b'mooring1')
# send position functions from catenary to FEM cable
m1.setNodesPositionFunction(cat1.s2xyz, cat1.ds2xyz)
# sets node positions of the cable