def test_eigs_beam():
"""Eigenvalues of a cantilever beam"""
nnodes = 10
x = np.linspace(0, np.pi, nnodes)
nodes = np.zeros((nnodes, 3))
nodes[:, 0] = range(nnodes)
nodes[:, 1] = x
cons = np.zeros((nnodes, 3))
cons[0, :] = -1
cons[:, 0] = -1
mats = np.array([[1.0, 1.0, 1.0, 1.0]])
elements = np.zeros((nnodes - 1, 5), dtype=int)
elements[:, 0] = range(nnodes - 1)
elements[:, 1] = 7
elements[:, 3] = range(nnodes - 1)
elements[:, 4] = range(1, nnodes)
assem_op, bc_array, neq = ass.DME(cons, elements, ndof_node=3)
stiff, mass = ass.assembler(elements, mats, nodes, neq, assem_op)
vals, _ = eigsh(stiff, M=mass, which="SM")
vals_analytic = np.array([
0.596864162694467, 1.49417561427335, 2.50024694616670,
3.49998931984744, 4.50000046151508, 5.49999998005609
])
assert np.allclose(vals**0.25, vals_analytic, rtol=1e-2)
def solids_GUI(compute_strains=False, plot_contours=True):
"""
Run a complete workflow for a Finite Element Analysis
Parameters
----------
compute_strains : Bool (optional)
Boolean variable to compute Strains and Stresses at nodes.
By default it is False.
plot_contours : Bool (optional)
Boolean variable to plot contours of the computed variables.
By default it is True.
Returns
-------
UC : ndarray (nnodes, 2)
Displacements at nodes.
E_nodes : ndarray (nnodes, 3), optional
Strains at nodes. It is returned when `compute_strains` is True.
S_nodes : ndarray (nnodes, 3), optional
Stresses at nodes. It is returned when `compute_strains` is True.
"""
folder = pre.initial_params()
start_time = datetime.now()
echo = False
#%% PRE-PROCESSING
nodes, mats, elements, loads = pre.readin(folder=folder)
if echo:
pre.echomod(nodes, mats, elements, loads, folder=folder)
DME , IBC , neq = ass.DME(nodes, elements)
print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
#%% SYSTEM ASSEMBLY
KG = ass.assembler(elements, mats, nodes, neq, DME)
RHSG = ass.loadasem(loads, IBC, neq)
#%% SYSTEM SOLUTION
UG = sol.static_sol(KG, RHSG)
if not(np.allclose(KG.dot(UG)/KG.max(), RHSG/KG.max())):
print("The system is not in equilibrium!")
end_time = datetime.now()
print('Duration for system solution: {}'.format(end_time - start_time))
#%% POST-PROCESSING
start_time = datetime.now()
UC = pos.complete_disp(IBC, nodes, UG)
E_nodes, S_nodes = None, None
if compute_strains:
E_nodes, S_nodes = pos.strain_nodes(nodes , elements, mats, UC)
if plot_contours:
pos.fields_plot(elements, nodes, UC, E_nodes=E_nodes, S_nodes=S_nodes)
end_time = datetime.now()
print('Duration for post processing: {}'.format(end_time - start_time))
print('Analysis terminated successfully!')
return UC, E_nodes, S_nodes if compute_strains else UC
def test_2_elements():
"""2x1 mesh cantilever beam"""
nodes = np.array([[0, 0, 0], [1, 1, 0], [2, 2, 0], [3, 0, 1], [4, 1, 1],
[5, 2, 1]])
cons = np.array([[-1, -1], [0, 0], [0, 0], [-1, -1], [0, 0], [0, 0]])
eles = np.array([[0, 1, 0, 0, 1, 4, 3], [1, 1, 0, 1, 2, 5, 4]])
loads = np.array([[2, 0, -0.5], [5, 0, -0.5]])
mater = np.array([[1.0, 0.3]])
assem_op, bc_array, neq = ass.DME(cons, eles)
stiff, _ = ass.assembler(eles, mater, nodes, neq, assem_op)
load_vec = ass.loadasem(loads, bc_array, neq)
disp = sol.static_sol(stiff, load_vec)
disp_complete = pos.complete_disp(bc_array, nodes, disp)
disp_analytic = 1 / 45 * np.array([[0, 0], [-273, -390], [-364, -1144],
[0, 0], [273, -390], [364, -1144]])
assert np.allclose(disp_complete, disp_analytic)
def test_4_elements():
"""2×2 mesh with uniaxial load"""
nodes = np.array([[0, 0, 0], [1, 2, 0], [2, 2, 2], [3, 0, 2], [4, 1, 0],
[5, 2, 1], [6, 1, 2], [7, 0, 1], [8, 1, 1]])
cons = np.array([[0, -1], [0, -1], [0, 0], [0, 0], [-1, -1], [0, 0],
[0, 0], [0, 0], [0, 0]])
eles = np.array([[0, 1, 0, 0, 4, 8, 7], [1, 1, 0, 4, 1, 5, 8],
[2, 1, 0, 7, 8, 6, 3], [3, 1, 0, 8, 5, 2, 6]])
loads = np.array([[3, 0, 1], [6, 0, 2], [2, 0, 1]])
mater = np.array([[1.0, 0.3]])
assem_op, bc_array, neq = ass.DME(cons, eles)
stiff, _ = ass.assembler(eles, mater, nodes, neq, assem_op)
load_vec = ass.loadasem(loads, bc_array, neq)
disp = sol.static_sol(stiff, load_vec)
disp_complete = pos.complete_disp(bc_array, nodes, disp)
disp_analytic = np.array([[0.6, 0.0], [-0.6, 0.0], [-0.6, 4.0], [0.6, 4.0],
[0.0, 0.0], [-0.6, 2.0], [0.0, 4.0], [0.6, 2.0],
[0.0, 2.0]])
assert np.allclose(disp_complete, disp_analytic)
def test_beams():
"""Beams with axial force"""
# Analytic problem
nodes = np.array([[0, 0.0, 0.0], [1, 0.0, 6.0], [2, 4.0, 6.0]])
cons = np.array([[-1, -1, -1], [0, 0, 0], [-1, -1, -1]])
mats = np.array([[200e9, 1.33e-4, 0.04]])
elements = np.array([[0, 8, 0, 0, 1], [1, 8, 0, 1, 2]])
loads = np.array([[1, -12000, -24000, -6000]])
assem_op, bc_array, neq = ass.DME(cons, elements, ndof_node=3)
stiff, _ = ass.assembler(elements,
mats,
nodes,
neq,
assem_op,
sparse=False)
load_vec = ass.loadasem(loads, bc_array, neq, ndof_node=3)
solution = sol.static_sol(stiff, load_vec)
solution_analytic = np.array([-6.29e-6, -1.695e-5, -0.13e-3])
assert np.allclose(solution, solution_analytic, rtol=1e-1)
def test_eigs_truss():
"""Eigenvalues of a bar"""
nnodes = 513
x = np.linspace(0, np.pi, nnodes)
nodes = np.zeros((nnodes, 3))
nodes[:, 0] = range(nnodes)
nodes[:, 1] = x
cons = np.zeros((nnodes, 2))
cons[:, 1] = -1
cons[0, 0] = -1
cons[-1, 0] = -1
mats = np.array([[1.0, 1.0, 1.0]])
elements = np.zeros((nnodes - 1, 5), dtype=int)
elements[:, 0] = range(nnodes - 1)
elements[:, 1] = 6
elements[:, 3] = range(nnodes - 1)
elements[:, 4] = range(1, nnodes)
assem_op, bc_array, neq = ass.DME(cons, elements)
stiff, mass = ass.assembler(elements, mats, nodes, neq, assem_op)
vals, _ = eigsh(stiff, M=mass, which="SM")
assert np.allclose(vals, np.linspace(1, 6, 6)**2, rtol=1e-2)
"""
from __future__ import division, print_function
import numpy as np
from datetime import datetime
import solidspy.preprocesor as pre
import solidspy.postprocesor as pos
import solidspy.assemutil as ass
import solidspy.solutil as sol
start_time = datetime.now()
#%% PRE-PROCESSING
nodes, mats, elements, loads = pre.readin()
DME , IBC , neq = ass.DME(nodes, elements)
print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
#%% SYSTEM ASSEMBLY
KG = ass.assembler(elements, mats, nodes, neq, DME, sparse=False)
RHSG = ass.loadasem(loads, IBC, neq)
##%% SYSTEM SOLUTION
UG = sol.static_sol(KG, RHSG)
if not(np.allclose(KG.dot(UG)/KG.max(), RHSG/KG.max())):
print("The system is not in equilibrium!")
end_time = datetime.now()
print('Duration for system solution: {}'.format(end_time - start_time))
def solids_GUI(plot_contours=True, compute_strains=False, folder=None):
"""
Run a complete workflow for a Finite Element Analysis
Parameters
----------
plot_contours : Bool (optional)
Boolean variable to plot contours of the computed variables.
By default it is True.
compute_strains : Bool (optional)
Boolean variable to compute Strains and Stresses at nodes.
By default it is False.
folder : string (optional)
String with the path to the input files. If not provided
it would ask for it in a pop-up window.
Returns
-------
UC : ndarray (nnodes, 2)
Displacements at nodes.
E_nodes : ndarray (nnodes, 3), optional
Strains at nodes. It is returned when `compute_strains` is True.
S_nodes : ndarray (nnodes, 3), optional
Stresses at nodes. It is returned when `compute_strains` is True.
"""
if folder is None:
folder = pre.initial_params()
start_time = datetime.now()
echo = False
# Pre-processing
nodes, mats, elements, loads = pre.readin(folder=folder)
if echo:
pre.echomod(nodes, mats, elements, loads, folder=folder)
DME, IBC, neq = ass.DME(nodes, elements)
print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
# System assembly
KG = ass.assembler(elements, mats, nodes, neq, DME)
RHSG = ass.loadasem(loads, IBC, neq)
# System solution
UG = sol.static_sol(KG, RHSG)
if not (np.allclose(KG.dot(UG) / KG.max(), RHSG / KG.max())):
print("The system is not in equilibrium!")
end_time = datetime.now()
print('Duration for system solution: {}'.format(end_time - start_time))
# Post-processing
start_time = datetime.now()
UC = pos.complete_disp(IBC, nodes, UG)
E_nodes, S_nodes = None, None
if compute_strains:
E_nodes, S_nodes = pos.strain_nodes(nodes, elements, mats, UC)
if plot_contours:
pos.fields_plot(elements, nodes, UC, E_nodes=E_nodes, S_nodes=S_nodes)
end_time = datetime.now()
print('Duration for post processing: {}'.format(end_time - start_time))
print('Analysis terminated successfully!')
return (UC, E_nodes, S_nodes) if compute_strains else UC
def test_dense_assem():
"""Tests for dense assembler"""
# 2 x 2 mesh
mats = np.array([[16, 1 / 3]])
nodes = np.array([[0, -1, -1], [1, 0, -1], [2, 1, -1], [3, -1, 0],
[4, 0, 0], [5, 1, 0], [6, -1, 1], [7, 0, 1], [8, 1, 1]])
elements = np.array([[0, 1, 0, 0, 1, 4, 3], [1, 1, 0, 1, 2, 5, 4],
[2, 1, 0, 3, 4, 7, 6], [3, 1, 0, 4, 5, 8, 7]])
DME = np.array(
[[0, 1, 2, 3, 8, 9, 6, 7], [2, 3, 4, 5, 10, 11, 8, 9],
[6, 7, 8, 9, 14, 15, 12, 13], [8, 9, 10, 11, 16, 17, 14, 15]],
dtype=np.int)
neq = 18
K_ass = ass.dense_assem(elements, mats, nodes, neq, DME)
K_exact = np.array(
[[8, 3, -5, 0, 0, 0, 1, 0, -4, -3, 0, 0, 0, 0, 0, 0, 0, 0],
[3, 8, 0, 1, 0, 0, 0, -5, -3, -4, 0, 0, 0, 0, 0, 0, 0, 0],
[-5, 0, 16, 0, -5, 0, -4, 3, 2, 0, -4, -3, 0, 0, 0, 0, 0, 0],
[0, 1, 0, 16, 0, 1, 3, -4, 0, -10, -3, -4, 0, 0, 0, 0, 0, 0],
[0, 0, -5, 0, 8, -3, 0, 0, -4, 3, 1, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 1, -3, 8, 0, 0, 3, -4, 0, -5, 0, 0, 0, 0, 0, 0],
[1, 0, -4, 3, 0, 0, 16, 0, -10, 0, 0, 0, 1, 0, -4, -3, 0, 0],
[0, -5, 3, -4, 0, 0, 0, 16, 0, 2, 0, 0, 0, -5, -3, -4, 0, 0],
[-4, -3, 2, 0, -4, 3, -10, 0, 32, 0, -10, 0, -4, 3, 2, 0, -4, -3],
[-3, -4, 0, -10, 3, -4, 0, 2, 0, 32, 0, 2, 3, -4, 0, -10, -3, -4],
[0, 0, -4, -3, 1, 0, 0, 0, -10, 0, 16, 0, 0, 0, -4, 3, 1, 0],
[0, 0, -3, -4, 0, -5, 0, 0, 0, 2, 0, 16, 0, 0, 3, -4, 0, -5],
[0, 0, 0, 0, 0, 0, 1, 0, -4, 3, 0, 0, 8, -3, -5, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, -5, 3, -4, 0, 0, -3, 8, 0, 1, 0, 0],
[0, 0, 0, 0, 0, 0, -4, -3, 2, 0, -4, 3, -5, 0, 16, 0, -5, 0],
[0, 0, 0, 0, 0, 0, -3, -4, 0, -10, 3, -4, 0, 1, 0, 16, 0, 1],
[0, 0, 0, 0, 0, 0, 0, 0, -4, -3, 1, 0, 0, 0, -5, 0, 8, 3],
[0, 0, 0, 0, 0, 0, 0, 0, -3, -4, 0, -5, 0, 0, 0, 1, 3, 8]])
assert np.allclose(K_ass, K_exact)
# Test for uel with all ones
def uel_ones(elcoord, par1, par0):
return np.ones((8, 8)), 8, 1
nodes = np.zeros((9, 5))
nodes[:, 0] = range(0, 9)
nodes[:, 1:3] = np.array([[0, 0], [1, 0], [2, 0], [0, 1], [1, 1], [2, 1],
[0, 2], [1, 2], [2, 2]])
elements = np.ones((4, 7), dtype=np.int)
elements[:, 0] = range(0, 4)
elements[:, 2] = 0
elements[:, 3:] = np.array([[0, 1, 4, 3], [1, 2, 5, 4], [3, 4, 7, 6],
[4, 5, 8, 7]])
mats = np.array([[1, 0.3]])
DME, IBC, neq = ass.DME(nodes, elements)
stiff = ass.assembler(elements,
mats,
nodes,
neq,
DME,
sparse=False,
uel=uel_ones)
stiff_exact = np.array(
[[1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0],
[1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0],
[1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0],
[1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1, 0, 0, 0, 0, 0, 0],
[0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0],
[0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0],
[1, 1, 1, 1, 0, 0, 2, 2, 2, 2, 0, 0, 1, 1, 1, 1, 0, 0],
[1, 1, 1, 1, 0, 0, 2, 2, 2, 2, 0, 0, 1, 1, 1, 1, 0, 0],
[1, 1, 2, 2, 1, 1, 2, 2, 4, 4, 2, 2, 1, 1, 2, 2, 1, 1],
[1, 1, 2, 2, 1, 1, 2, 2, 4, 4, 2, 2, 1, 1, 2, 2, 1, 1],
[0, 0, 1, 1, 1, 1, 0, 0, 2, 2, 2, 2, 0, 0, 1, 1, 1, 1],
[0, 0, 1, 1, 1, 1, 0, 0, 2, 2, 2, 2, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0],
[0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 0, 0],
[0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1],
[0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 1, 1, 1, 1, 2, 2, 1, 1],
[0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1],
[0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1]])
assert np.allclose(stiff, stiff_exact)
# Test assembly of a truss
length = 10 * np.cos(np.pi / 6)
nodes = np.array([[0.0, length, 0.0, 0.0, 0.0], [1.0, 0.0, 5.0, -1.0, 0.0],
[2.0, 0.0, 0.0, -1.0, -1.0]])
mats = np.array([[1e6, 0.01]])
elements = np.array([[0, 6, 0, 2, 0], [1, 6, 0, 1, 0], [2, 6, 0, 1, 2]])
DME, IBC, neq = ass.DME(nodes, elements)
stiff = ass.assembler(elements, mats, nodes, neq, DME, sparse=False)
stiff_exact = 250 * np.array(
[[8 / np.sqrt(3) + 3, -np.sqrt(3),
np.sqrt(3)], [-np.sqrt(3), 1, -1], [np.sqrt(3), -1, 9]])
assert np.allclose(stiff, stiff_exact)
np.savetxt(os.path.join(folder,"loads.txt"),loads,fmt="%.3f",delimiter="\t")
np.savetxt(os.path.join(folder,"eles.txt"),elements,fmt="%i",delimiter="\t")
t2=time.time()
print("grid assembly ", t2-t1)
start_time = dt.now()
echo = False
compute_strains=True
plot_contours=False
nodes, mats, elements, loads = pre.readin(folder=folder)
if echo:
pre.echomod(nodes, mats, elements, loads, folder=folder)
DME, IBC, neq = ass.DME(nodes, elements) # boundary conditions asembly??
# DME
#IBC list of "equations in x y direction for each node, -1 indicates no equations of movement, as completly fixed --> related to boundary conditions
# neq total number of equations
# DME is like list of independent equations per element(square, so just rearanged IBC for elements,side node zeros are at the end because of fixed length( for other element shape=
#
#
# print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
# System assembly
t1=time.time()
KG = ass.assembler(elements, mats, nodes, neq, DME,sparse=False)
def solids_auto(data, plot_contours=True, compute_strains=False):
"""
Run a complete workflow for a Finite Element Analysis
Parameters
----------
data : dict
Simulation data composed of nodes, constrains, elements,
materials and loads.
plot_contours : Bool (optional)
Boolean variable to plot contours of the computed variables.
By default it is True.
compute_strains : Bool (optional)
Boolean variable to compute Strains and Stresses at nodes.
By default it is False.
Returns
-------
UC : ndarray (nnodes, 2)
Displacements at nodes.
E_nodes : ndarray (nnodes, 3), optional
Strains at nodes. It is returned when `compute_strains` is True.
S_nodes : ndarray (nnodes, 3), optional
Stresses at nodes. It is returned when `compute_strains` is True.
"""
# Retrieving data
nodes = data["nodes"]
cons = data["cons"]
elements = data["elements"]
mats = data["mats"]
loads = data["loads"]
# Pre-processing
assem_op, bc_array, neq = ass.DME(cons, elements)
print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
# System assembly
stiff_mat, _ = ass.assembler(elements, mats, nodes, neq, assem_op)
rhs_vec = ass.loadasem(loads, bc_array, neq)
# System solution
start_time = datetime.now()
disp = sol.static_sol(stiff_mat, rhs_vec)
if not np.allclose(
stiff_mat.dot(disp) / stiff_mat.max(), rhs_vec / stiff_mat.max()):
print("The system is not in equilibrium!")
end_time = datetime.now()
print('Duration for system solution: {}'.format(end_time - start_time))
# Post-processing
start_time = datetime.now()
disp_complete = pos.complete_disp(bc_array, nodes, disp)
strain_nodes, stress_nodes = None, None
if compute_strains:
strain_nodes, stress_nodes = pos.strain_nodes(nodes, elements, mats,
disp_complete)
if plot_contours:
pos.fields_plot(elements,
nodes,
disp_complete,
E_nodes=strain_nodes,
S_nodes=stress_nodes)
end_time = datetime.now()
print('Duration for post processing: {}'.format(end_time - start_time))
print('Analysis terminated successfully!')
if compute_strains:
return (disp_complete, strain_nodes, stress_nodes)
else:
return disp_complete
def solids_GUI(plot_contours=True, compute_strains=False, folder=None):
"""
Run a complete workflow for a Finite Element Analysis
Parameters
----------
plot_contours : Bool (optional)
Boolean variable to plot contours of the computed variables.
By default it is True.
compute_strains : Bool (optional)
Boolean variable to compute Strains and Stresses at nodes.
By default it is False.
folder : string (optional)
String with the path to the input files. If not provided
it would ask for it in a pop-up window.
Returns
-------
UC : ndarray (nnodes, 2)
Displacements at nodes.
E_nodes : ndarray (nnodes, 3), optional
Strains at nodes. It is returned when `compute_strains` is True.
S_nodes : ndarray (nnodes, 3), optional
Stresses at nodes. It is returned when `compute_strains` is True.
"""
if folder is None:
folder = pre.initial_params()
start_time = datetime.now()
echo = False
# Pre-processing
nodes, mats, elements, loads = pre.readin(folder=folder)
if echo:
pre.echomod(nodes, mats, elements, loads, folder=folder)
assem_op, bc_array, neq = ass.DME(nodes[:, -2:], elements)
print("Number of nodes: {}".format(nodes.shape[0]))
print("Number of elements: {}".format(elements.shape[0]))
print("Number of equations: {}".format(neq))
# System assembly
stiff_mat, _ = ass.assembler(elements, mats, nodes[:, :3], neq, assem_op)
rhs_vec = ass.loadasem(loads, bc_array, neq)
# System solution
disp = sol.static_sol(stiff_mat, rhs_vec)
if not np.allclose(
stiff_mat.dot(disp) / stiff_mat.max(), rhs_vec / stiff_mat.max()):
print("The system is not in equilibrium!")
end_time = datetime.now()
print('Duration for system solution: {}'.format(end_time - start_time))
# Post-processing
start_time = datetime.now()
disp_complete = pos.complete_disp(bc_array, nodes, disp)
strain_nodes, stress_nodes = None, None
if compute_strains:
strain_nodes, stress_nodes = pos.strain_nodes(nodes, elements, mats,
disp_complete)
if plot_contours:
pos.fields_plot(elements,
nodes,
disp_complete,
E_nodes=strain_nodes,
S_nodes=stress_nodes)
end_time = datetime.now()
print('Duration for post processing: {}'.format(end_time - start_time))
print('Analysis terminated successfully!')
if compute_strains:
return (disp_complete, strain_nodes, stress_nodes)
else:
return disp_complete