Thermal expansion defined by a predefined temperature field is tested for
the following material models: isotropic elasticity, orthotropic elasticity,
anisotropic elasticity, lamina, hyperelasticity with polynomial and Ogden
forms, hyperelasticity with Arruda-Boyce and Van der Waals forms, hyperfoam,
Mises plasticity, Drucker-Prager plasticity, Hill's potential plasticity,
crushable foam plasticity with volumetric hardening, crushable foam plasticity
with isotropic hardening, ductile failure plasticity, rate-dependent Hill's
potential plasticity, rate-dependent Mises plasticity, Drucker-Prager/Cap
plasticity, porous metal plasticity, visco-hyperelasticity with polynomial and
Ogden forms, visco-hyperelasticity with Arruda-Boyce and Van der Waals forms,
and visco-hyperfoam.
Problem description
The verification tests consist of a set of single-element tests that include a combination of all
the available elements with all the available materials. All elements are loaded by
ramping up the temperature from an initial value of 0° to a final value of 100°. The
undeformed meshes are shown in Figure 1 for the elasticity models, Figure 2 for the inelasticity models, and Figure 3 for the viscoelasticity models. Material properties are listed in Table 1 for the elastic materials and in Table 2 for the inelastic materials. The thermal expansion coefficient for all materials
is 0.00005.
The degrees of freedom in the vertical direction are constrained for all the
nodes, and deformation is allowed only in the horizontal direction. Nodes
associated with elements C3D8R and C3D10M are constrained in the out-of-plane direction, which causes a
plane strain condition to apply for these elements.
Results and discussion
The time history plots for isotropic elasticity, Mises plasticity, and
viscoelasticity for all of the elements are shown in
Figure 4,
Figure 5,
and
Figure 6,
respectively, except for pipe elements, whose results are consistent with beam
elements.
Visco-Van der
Waals hyperelasticity (density=1000)
uniaxial test
(155060, 0.1338)
... ...
(6.424 × 106, 6.6433)
biaxial test
(93840, 0.02)
... ...
(2.465 × 106, 3.45)
planar test
(60000, 0.0690)
... ...
(1.82 × 106, 4.0621)
0.901001
0.0
0.99
70
4.92
215
Table 2. Material properties for inelastic materials.
Material
Properties
Value
Mises plasticity
(density=8032)
E
193.1 ×
109
0.3
206893
H
206893
Drucker
plasticity (density=1000)
E
2.0 ×
107
0.3
40000
H
40000
40
K
1.0
20.0
Hill's
plasticity (density=2500)
E
1.0 × 109
0.3
1.0 × 106
H
4.0 × 105
1.5
1.0
1.0
1.0
1.0
1.0
Crushable foam
with volumetric hardening (density=500)
E
3.0 × 106
0.0
k
1.1
0.1
hardening
(2.2× 105, 0.0)
... ...
(6.88× 105, 10.0)
Crushable foam
with isotropic hardening (density=500)
E
3.0 × 106
0.0
k
1.1
0.2983
hardening
(2.2× 105, 0.0)
... ...
(6.88× 105, 10.0)
Ductile failure
(density=5800)
E
2.0 × 108
0.3
2.0 × 105
H
4.0 × 105
0.5
Mises plasticity
(density=8032)(rate dependent)
E
193.1 × 109
0.3
206893
H
206893
D
1000
p
2.0
Hill's plasticity
(density=2500)(rate dependent)
E
1.0 × 109
0.3
1.0 × 106
H
4.0 × 105
1.5
1.0
1.0
1.0
1.0
1.0
D
4000
p
6.0
Drucker-Prager/Cap plasticity(density=0.0024)
E
30000
0.3
d
100
37.67
R
0.1
0.0
0.01
hardening
(20.96, 0)
... ...
(655.6, 0.00249)
Porous metal
plasticity(density=7.7 × 107)
E
2.0 × 1011
0.33
7.5 × 108
H
0.0
1.0
1.25
1.0
0.1
0.06
0.04
0.8
0.5
Figures
Figure 1. Simple expansion test for elastic materials. Figure 2. Simple expansion test for inelastic materials. Figure 3. Simple expansion test for viscoelastic materials. Figure 4. Mises stress versus time for isotropic elasticity. Figure 5. Mises stress versus time for Mises plasticity. Figure 6. Mises stress versus time for viscoelasticity.