UMFPACK error: out of memory despite system having free memory

12

Hi. I have used this solve to fix it the same problem, and its work fine to calculate de Displacement solution in my model. But, i still need to calculate the stress tensor and it give me a error, i think, for the model size.
The code is the following and if i activate the lines to calculate the stress it don’t work.:

from dolfin import*
from mshr import*
from fenics import*
from ufl import nabla_div
import matplotlib.pyplot as plt
import numpy as np

mesh = Mesh("Caseron_actual.xml")
#plot(mesh);
#Scaled Variables
E = Constant(20e3) #Módulo de Young
nu = Constant(0.3) #Radio de Poisson
mu = E/(2*(1+nu)) #Módulo de cizalle
lambda_ = E*nu/((1+nu)*(1-2*nu)) #Lamé
rho = Constant(0.027) #densidad

# Strain function
def epsilon(u):
    return sym(nabla_grad(u))

# Stress function
def sigma(u):
    return lambda_*nabla_div(u)*Identity(3) + 2*mu*epsilon(u)
# lambda is a reserved python keyword, naming convention recommends using a single trailing underscore for such cases

#Load
g_z = 0.0
b_z = -rho
g = Constant((0.0,g_z,0.0))
b = Constant((0.0,0.0,b_z))

#Function Spaces
V = VectorFunctionSpace(mesh, "P", 2)
u_tr = TrialFunction(V)
u_test = TestFunction(V)

a = inner(sigma(u_tr),epsilon(u_test))*dx #bilineal form
l = dot(b,u_test)*dx + dot(g, u_test)*ds #lineal form

x_max = 1216.0
y_max = 929.
tol=1e-8
def bottom(x, on_boundary):
    return (on_boundary and near(x[2],0,tol))
bc1 =DirichletBC(V.sub(2), Constant(0.),bottom)

def left(x, on_boundary):
    return (on_boundary and near(x[0], 0,tol))
bc2 =DirichletBC(V.sub(0), Constant(0.),left)

def right(x, on_boundary):
    return (on_boundary and near(x[0], x_max,tol))
bc3 =DirichletBC(V.sub(0), Constant(0.),right)

def north(x, on_boundary):
    return (on_boundary and near(x[1], y_max,tol))
bc4 =DirichletBC(V.sub(1), Constant(0.),north)

def south(x, on_boundary):
    return (on_boundary and near(x[1], 0,tol))
bc5 =DirichletBC(V.sub(1), Constant(0.),south)
bc=[bc1,bc2,bc3,bc4,bc5]

u = Function(V)
#problem = LinearVariationalProblem(a, l, u, bc)
#solver = LinearVariationalSolver(problem)
#solver.solve();
solve(a==l, u, bc, solver_parameters={'linear_solver' : 'mumps'})

#Vsig = TensorFunctionSpace(mesh, "DG",degree=1)
#sig = Function(Vsig, name="Cauchy_Stress")
#sig.assign(project(-sigma(u), Vsig));

file_results = XDMFFile("Verde_CA.xdmf")
file_results.parameters["flush_output"] = True
file_results.parameters["functions_share_mesh"] = True
file_results.write(u, 0.)
#file_results.write(sig, 0.)

I hope you can help me