/FAIL/ENERGY
Block Format Keyword Describes an energy density failure model.
Format
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| /FAIL/ENERGY/mat_ID/unit_ID | |||||||||
| E1 | E2 | fct_ID | Xscale | I_Dam | |||||
Optional Line
| (1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
|---|---|---|---|---|---|---|---|---|---|
| fail_ID |
Definitions
| Field | Contents | SI Unit Example |
|---|---|---|
| mat_ID | Material identifier. (Integer, maximum 10 digits) |
|
| unit_ID | Unit Identifier. (Integer, maximum 10 digits) |
|
| E1 | Maximum energy density. 2 Default = 130 (Real) |
|
| E2 | Failure energy density. 2 Default = 230 (Real) |
|
| I_Dam | Damage calculation flag. 4
Default = 1 (Integer) |
|
| fct_ID | Function identifier for
. It is the function of energy density E1 and E2 scaling factor versus strain rate. (Integer) |
|
| Xscale | Scale factor for abscissa of the
function. Default = 1.0 (Real) |
|
| fail_ID | Failure criteria
identifier. 3 (Integer, maximum 10 digits) |
Example (Metal)
In this example, fail_ID
is used to scale the energy density (E1 and
E2)
for different test strain
rates.
#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/1
unit for mat
# MUNIT LUNIT TUNIT
Mg mm s
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/PLAS_TAB/1/1
Metal
# RHO_I
2.788714E-9 0
# E Nu Eps_p_max Eps_t Eps_m
68000 .3 0 0 0
# N_funct F_smooth C_hard F_cut Eps_f
1 0 0 0 0
# fct_IDp Fscale Fct_IDE EInf CE
0 1 0 0 0
# func_ID1 func_ID2 func_ID3 func_ID4 func_ID5
2
# Fscale_1 Fscale_2 Fscale_3 Fscale_4 Fscale_5
0
# Eps_dot_1 Eps_dot_2 Eps_dot_3 Eps_dot_4 Eps_dot_5
0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FAIL/ENERGY/1/1
# E1 E2 funct_ID Xscale I_Dam
0.3 0.34 18 1
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FUNCT/18
scale factor for energy density E1 and E2
# strain rate scale factor
# X Y
0 1
50 0.5
10000 0.5
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/FUNCT/2
True Stress-True plastic strain
# X Y
0 124
.01 150
.02 165
.04 184
.06 196
.08 203
.1 206
.12 210
.14 213
.16 217
.18 220
.5 240
1000 240
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|Comments
- The element is
deleted, if D=1 for one integration point.
(1) - The energy density is the current internal
energy of the element divided by the current element volume. The value will be different
than the element time history /TH/element Internal energy (IE) which is
the current internal energy divided by the "initial" element volume.
Figure 1. Energy Density Model Failure - The fail_ID is used with /STATE/BRICK/FAIL and /INIBRI/FAIL. There is no default value. If the line is blank, no value will be output for failure model variables in the /INIBRI/FAIL (written in .sta file with /STATE/BRICK/FAIL option).
- The I_Dam option improves damage calculation and stability calculating damage, it is not available for shell elements and material laws N° < 29 . It is available for the /MAT/LAW25 (CRASURV) law, if using /PROP/TYPE51 or /PLY and /STACK options.