Hello guys. I really appreciate with someone could help me.

I’m trying to solve the following contour problem:

\varsigma \int_{\Gamma_s} \nabla : \sigma^s (u) ds = \int_{\Gamma_s} w P.n dx

using the following structure: (giving just the essential)

class Interface(SubDomain):

def inside(self, x, on_boundary):

dy = x[1]

dz = x[2]

dr = (dydy + dzdz)**0.5

zeta = DOLFIN_EPS + 1.0E-3

return dr >( ri - zeta) and between(x[0], (0.2,4.0))parts = MeshFunction(“size_t”, mesh, mesh.topology().dim()-1, 0)

Interface().mark(parts,4)

ds = Measure(‘ds’, domain=mesh,subdomain_data=parts)timeseries_p = TimeSeries(‘pressure_series’)

timeseries_p.retrieve(pr.vector(), t)pavg = (assemble(pr*ds(4))/(assemble(Constant(1.0)*ds(4)))) #mean pressure in the interface

w1 = TestFunction(W.sub(0))

u1 = TrialFunction(W.sub(0))

us = Function(W.sub(0).collapse())Fhp = inner(pavg*n, w1)

ds(4) - qsiinner(sigma_s(u1),epsilon_s(w1))*ds(4)

ahp, Lhp = system(Fhp)

Ahp, bhp = assemble(ahp), assemble(Lhp)

solve(Ahp, us.vector(), bhp, ‘gmres’, ‘ilu’)

and I’m stuck with the following error:

Error: Unable to successfully call PETSc function ‘KSPSolve’.

*** Reason: PETSc error code is: 73 (Object is in wrong state).

*** Where: This error was encountered inside /tmp/dolfin/dolfin/la/PETScKrylovSolver.cpp.

Someone could help me?