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JuliaFEM.jl/test/test_elasticity_solver.jl
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# This file is a part of JuliaFEM.
# License is MIT: see https://github.com/JuliaFEM/JuliaFEM.jl/blob/master/LICENSE.md
using FactCheck
using Logging
@Logging.configure(level=INFO)
using JuliaFEM.elasticity_solver: solve_elasticity_increment!
function one_elem_fixture()
X = [0.0 0.0; 10.0 0.0; 10.0 1.0; 0.0 1.0]'
elmap = [1; 2; 3; 4]
nodalloads = [0 0; 0 0; 0 -2; 0 0]'
@debug("nodal loads:\n", nodalloads)
dirichletbc = [0 0; NaN NaN; NaN NaN; 0 0]'
E = 90
nu = 0.25
mu = E/(2*(1+nu))
la = E*nu/((1+nu)*(1-2*nu))
la = 2*la*mu/(la + 2*mu)
la = la*ones(1, 4)
mu = mu*ones(1, 4)
u = zeros(2, 4)
du = zeros(2, 4)
N(xi) = [
(1-xi[1])*(1-xi[2])/4
(1+xi[1])*(1-xi[2])/4
(1+xi[1])*(1+xi[2])/4
(1-xi[1])*(1+xi[2])/4
]
dNdξ(ξ) = [-(1-ξ[2])/4.0 -(1-ξ[1])/4.0
(1-ξ[2])/4.0 -(1+ξ[1])/4.0
(1+ξ[2])/4.0 (1+ξ[1])/4.0
-(1+ξ[2])/4.0 (1-ξ[1])/4.0]
ipoints = 1/sqrt(3)*[-1 -1; 1 -1; 1 1; -1 1]
iweights = [1 1 1 1]
return (X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights)
end
facts("test solve elasticity increment") do
(X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights) = one_elem_fixture()
for i=1:10
solve_elasticity_increment!(X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights)
@debug("increment:\n",du)
u += du
if norm(du) < 1.0e-9
break
end
end
@debug("solution\n",u)
@fact u[2, 3] => roughly(-2.222244754401764) # Tested against Elmer solution
end
facts("test solve elasticity increment rot 30") do
(X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights) = one_elem_fixture()
phi = 30/180*pi
rmat = [cos(phi) -sin(phi); sin(phi) cos(phi)]
X = rmat*X
nodalloads = rmat*nodalloads
for i=1:10
solve_elasticity_increment!(X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights)
@debug("increment:\n",du)
u += du
if norm(du) < 1.0e-9
break
end
end
u = rmat'*u
@debug("solution\n",u)
@fact u[2, 3] => roughly(-2.222244754401764) # Tested against Elmer solution
end
facts("test solve elasticity increment, two elements") do
X = Float64[0 0; 1 0; 2 0; 0 1; 1 1; 2 1]'
elmap = [1 2 5 4; 2 3 6 5]'
nodalloads = [0 0; 0 0; 0 0; 0 0; 0 0; -3 0]'
@debug("nodal loads:\n", nodalloads)
dirichletbc = [0 0; NaN NaN; NaN NaN; 0 0; NaN NaN; NaN NaN]'
dim, nnodes = size(X)
E = 90
nu = 0.25
mu = E/(2*(1+nu))
la = E*nu/((1+nu)*(1-2*nu))
la = 2*la*mu/(la + 2*mu)
la = la*ones(1, nnodes)
mu = mu*ones(1, nnodes)
u = zeros(dim, nnodes)
du = zeros(dim, nnodes)
N(xi) = [
(1-xi[1])*(1-xi[2])/4
(1+xi[1])*(1-xi[2])/4
(1+xi[1])*(1+xi[2])/4
(1-xi[1])*(1+xi[2])/4
]
dNdξ(ξ) = [-(1-ξ[2])/4.0 -(1-ξ[1])/4.0
(1-ξ[2])/4.0 -(1+ξ[1])/4.0
(1+ξ[2])/4.0 (1+ξ[1])/4.0
-(1+ξ[2])/4.0 (1-ξ[1])/4.0]
ipoints = 1/sqrt(3)*[-1 -1; 1 -1; 1 1; -1 1]
iweights = [1 1 1 1]
for i=1:10
solve_elasticity_increment!(X, u, du, elmap, nodalloads, dirichletbc,
la, mu, N, dNdξ, ipoints, iweights)
@debug("increment:\n",du)
u += du
if norm(du) < 1.0e-9
break
end
end
@debug("solution\n",u)
# Known to fail, test against elmer.
@pending u[2, 6] => roughly(:something)
end
using JuliaFEM.elasticity_solver: interpolate
facts("test interpolation of different field variables") do
N(xi) = [
(1-xi[1])*(1-xi[2])/4
(1+xi[1])*(1-xi[2])/4
(1+xi[1])*(1+xi[2])/4
(1-xi[1])*(1+xi[2])/4
]
dNdξ(ξ) = [-(1-ξ[2])/4.0 -(1-ξ[1])/4.0
(1-ξ[2])/4.0 -(1+ξ[1])/4.0
(1+ξ[2])/4.0 (1+ξ[1])/4.0
-(1+ξ[2])/4.0 (1-ξ[1])/4.0]
F1 = [36.0, 36.0, 36.0, 36.0]
F2 = [36.0 36.0 36.0 36.0]
F3 = F2'
F4 = [0.0 0.0; 10.0 0.0; 10.0 1.0; 0.0 1.0]'
F5 = F4'
F6 = [36, 36, 36, 36]
@fact interpolate(F1, N, [0.0, 0.0]) => 36.0
@fact interpolate(F2, N, [0.0, 0.0]) => 36.0
@fact interpolate(F3, N, [0.0, 0.0]) => 36.0
@fact interpolate(F4, N, [0.0, 0.0]) => [5.0; 0.5]
@fact interpolate(F5, N, [0.0, 0.0]) => [5.0; 0.5]
@fact interpolate(F5, dNdξ, [0.0, 0.0]) => [5.0 0.0; 0.0 0.5]
@fact interpolate(F6, N, [0.0, 0.0]) => 36
end
using JuliaFEM.elasticity_solver: assemble!
facts("test assembly of global matrix for 1 dim/node case") do
I = Int64[]
J = Int64[]
V = Float64[]
ke = [3 1; 1 1]
eldofs = [1, 2]
assemble!(ke, eldofs, I, J, V)
ke = [4 2; 2 3]
eldofs = [2, 4]
assemble!(ke, eldofs, I, J, V)
S = full(sparse(I, J, V))
@fact S => [3.0 1.0 0.0 0.0
1.0 5.0 0.0 2.0
0.0 0.0 0.0 0.0
0.0 2.0 0.0 3.0]
end
facts("test assembly of global vector for 1 dim/node case") do
I = Int64[]
V = Float64[]
fe = [1;2]
eldofs = [1, 2]
assemble!(fe, eldofs, I, V)
fe = [3;1]
eldofs = [2, 4]
assemble!(fe, eldofs, I, V)
S = full(sparsevec(I, V))
@fact S => [1.0 5.0 0.0 1.0]'
end
facts("test assembly of global matrix for 2 dim/node case") do
# provide "convienence" function, if given only nodal connectivity
# automatically find out dimension and "extend" matrix to full
I = Int64[]
J = Int64[]
V = Float64[]
ke = reshape(1:16, 4, 4)
eldofs = [1, 2]
assemble!(ke, eldofs, I, J, V)
eldofs = [2, 3]
assemble!(2*ke, eldofs, I, J, V)
expected = zeros(6, 6)
expected[1:4,1:4] += ke
expected[3:6,3:6] += 2*ke
S = full(sparse(I, J, V))
@fact S => expected
end
facts("test assembly of global vector for 2 dim/node case") do
# provide "convienence" function, if given only nodal connectivity
# automatically find out dimension and "extend" matrix to full
I = Int64[]
J = Int64[]
V = Float64[]
fe = [1, 2, 3, 4]
eldofs = [1, 2]
assemble!(fe, eldofs, I, V)
eldofs = [2, 3]
assemble!(2*fe, eldofs, I, V)
S = full(sparsevec(I, V))
expected = [1.0 2.0 5.0 8.0 6.0 8.0]'
@fact S => expected
end
using JuliaFEM.elasticity_solver: eliminate_boundary_conditions
facts("remove boundary conditions from matrix with 2 dof/node") do
# create sparse matrix 4x4 with some data
# 4x4 Array{Int64,2}:
# 1 5 9 13
# 2 6 10 14
# 3 7 11 15
# 4 8 12 16
A = sparse(reshape(1:4*4, 4, 4))
I, J, V = findnz(A)
# we plan to eliminate first dof of first node and second dof of second node
# expected output would be
# 6 10
# 7 11
dirichletbc = [0 NaN; NaN 0]'
I, J, V = eliminate_boundary_conditions(dirichletbc, I, J, V)
A2 = full(sparse(I, J, V))
@fact A2 => [6 10; 7 11]
end
facts("remove boundary conditions from vector with 2 dof/node") do
# create sparse vector dim 4 with some data
# 1 2 3 4 '
A = sparsevec([1, 2, 3, 4])
I, J, V = findnz(A)
# we plan to eliminate first dof of first node and second dof of second node
# expected output would be
# 2 3
dirichletbc = [0 NaN; NaN 0]'
I, V = eliminate_boundary_conditions(dirichletbc, I, V)
A2 = full(sparsevec(I, V))
@fact A2 => [2 3]'
end
facts("test that elimination of non-homogeneous dirichlet boundary conditions raises error because they are not supported atm") do
A = sparse(reshape(1:4*4, 4, 4))
I, J, V = findnz(A)
dirichletbc = [0 1; NaN 0]'
@fact_throws I, J, V = eliminate_boundary_conditions(dirichletbc, I, J, V)
A = sparsevec([1, 2, 3, 4])
I, J, V = findnz(A)
@fact_throws I, V = eliminate_boundary_conditions(dirichletbc, I, V)
end