return Min(nu_out, 2e15) # would introduce a viscosity limit
nu = visc(u)
epsilon = sym(grad(u))
F = (2*nu*inner(epsilon, grad(v)) - div(u)*q - div(v)*p)*dx - inner(v, f)*dx
dF = derivative(F, w)
pde = NonlinearVariationalProblem(F, w, bcs, dF)
solver = NonlinearVariationalSolver(pde)
solver.parameters["symmetric"] = True
solver.parameters["newton_solver"]["maximum_iterations"] = 80
solver.parameters["newton_solver"]["error_on_nonconvergence"] = False
solver.parameters["newton_solver"]["relaxation_parameter"] = 0.6
solver.parameters["newton_solver"]["relative_tolerance"] = 1E-4
solver.parameters["newton_solver"]["linear_solver"] = 'superlu_dist'
solver.solve()
(u, p) = w.split(deepcopy=True)
# Save the final solution
ufilename = "velocity_%s" % (fname)
fu = HDF5File(mesh.mpi_comm(),os.path.join(data_dir, ufilename+".hdf5"), 'w')
fu.write(u, "/velocity")
# Save the final solution for visualisation
save_pvd("3D_velocity_%s" % (fname), u)
print "end of ice dynamics"
mb_func = set_mb(s_new, Q3, dofsQ3, dofsQ3_x)
# if constant value shall be set
#mb_func = Function(Q3)
#mb_func.assign(Constant(0.0))
# Set velocity on the computational mesh
v_new = set_velocity(velocity, s_new, s_new_bed_ini, Q3, V3, dofV3_x, dofsV3,
bed_diff1)
v_vert = set_verticalvelocity(velocity, s_new, s_new_bed_ini, Q3, dofsQ3,
dofsQ3_x, bed_diff1)
# Compute exptected mass change due to mass balance rate field
[mb_start, mb0_start] = mb_change(mb_func, hice_start, dt_ADV, Q3)
mb_mass0 = hice_t0 - assemble(mb0_start * dx)
# Save fields for visualisation
# save_pvd("rmesh_hicestart", hice_start, pvd_number=tna)
save_pvd("rmesh_ft0", mb_func)
# save_pvd("rmesh_snew", s_new, pvd_number=tna)
save_pvd("rmesh_vnew", v_new, pvd_number=tna)
save_pvd("rmesh_vert", v_vert, pvd_number=tna)
# save_pvd("rmesh_ice", h_ice1, pvd_number=tna)
# save_pvd("rmesh_bed", s_new_bed, pvd_number=tna)
# Compute surface gradient
DG = VectorFunctionSpace(Rmesh, 'DG', 0)
grad2 = project(grad(s_new), DG)
save_pvd("rmesh_grad2", grad2, pvd_number=tna)
# -------------------- START of SURFACE EVOLUTION -------------------------
# Perform computation on 2D computational mesh
# Required in SUPG stabilisation
h = CellSize(Rmesh)
[mb_start, mb0_start] = mb_change(mb_func, hice_start, dt_ADV, Q3)
mb_mass0 = hice_t0 - assemble(mb0_start * dx)
# Save fields for visualisation
# save_pvd("rmesh_hicestart", hice_start, pvd_number=tna)
# save_pvd("rmesh_ft0", mb_func)
# save_pvd("rmesh_snew", s_new, pvd_number=tna)
# save_pvd("rmesh_vnew", v_new, pvd_number=tna)
# save_pvd("rmesh_vert", v_vert, pvd_number=tna)
# save_pvd("rmesh_ice", h_ice1, pvd_number=tna)
# save_pvd("rmesh_bed", s_new_bed, pvd_number=tna)
# Compute surface gradient
DG = VectorFunctionSpace(Rmesh, 'DG', 0)
grad2 = project(grad(s_new), DG)
save_pvd("rmesh_grad2", grad2, pvd_number=tna)
# Interpolate all parameters into DG FunctionSpace
Q_dg = FunctionSpace(Rmesh, "DG", 1)
V_dg = VectorFunctionSpace(Rmesh, "DG", 1)
snew_dg = interpolate(s_new, Q_dg)
snewbed_dg = interpolate(s_new_bed, Q_dg)
mbfunc_dg = interpolate(mb_func, Q_dg)
vnew_dg = interpolate(v_new, V_dg)
vvert_dg = interpolate(v_vert, Q_dg)
# -------------------- START of SURFACE EVOLUTION -------------------------
# Perform computation on 2D computational mesh
# Required in SUPG stabilisation
h = CellSize(Rmesh)
n = FacetNormal(Rmesh)
class BoundaryEast(SubDomain):
def inside(self, x, on_boundary):
return on_boundary and (near(x[0], nx2))
north = BoundaryNorth()
south = BoundarySouth()
west = BoundaryWest()
east = BoundaryEast()
# Mark boundaries
north.mark(boundaries, 106)
south.mark(boundaries, 104)
west.mark(boundaries, 105)
east.mark(boundaries, 103)
# Save mesh to hdf5
m3filename = fname
fu10 = HDF5File(mesh.mpi_comm(), os.path.join(data_dir, m3filename + ".hdf5"),
'w')
fu10.write(mesh, "/mesh")
#fu10.write(subdomains, "/subdomains")
fu10.write(boundaries, "/boundaries")
# Save for visualisation
save_pvd("3D_mesh_%s" % (fname), mesh)
#save_pvd("3D_boundaries_%s" % (fname), boundaries)
print "read mesh done - t1: ", t1, mesh.hmin()