/FAIL/ENERGY

Format


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/FAIL/ENERGY/`mat_ID`/`unit_ID`
`E`₁		`E`₂		`fct_ID`	`Xscale`		`I_Dam`

Optional Line


(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
`fail_ID`

Definition


Field	Contents	SI Unit Example
`mat_ID`	Material identifier. (Integer, maximum 10 digits)
`unit_ID`	Unit identifier. (Integer, maximum 10 digits)
`E`₁	Maximum energy density. 2 Default = 1³⁰ (Real)	$[\frac{J}{m^{3}}]$
`E`₂	Failure energy density. 2 Default = 2³⁰ (Real)	$[\frac{J}{m^{3}}]$
`I_Dam`	Damage calculation flag. 4 =1 Only forces are reduced. The stress tensor is not damaged. =2 Stress tensor is reduced (used before version 2018). Default = 1 (Integer)
`fct_ID`	Function identifier for $f (\dot{ε})$ . It is the function of energy density `E`₁ and `E`₂ scaling factor versus strain rate. (Integer)
`Xscale`	Scale factor for abscissa of the function. Default = 1.0 (Real)	$[\frac{1}{s}]$
`fail_ID`	Failure criteria identifier. 3 (Integer, maximum 10 digits)

▸Example (Metal)

In this example, is used to scale the energy density ( and ) 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.
$D = \frac{E - E_{1}}{E_{2} - E_{1}}$
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.