Iform = 0
Block Format Keyword The material law is based on a diffusive interface technique.
To get sharper interfaces between submaterial zones, refer to /ALE/MUSCL.
- P
- Positive for a compression and negative for traction.
Where, mean that the EOS is linear for an expansion and cubic for a compression.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/MAT/LAW51/mat_ID/unit_ID | |||||||||
mat_title | |||||||||
Blank | |||||||||
Iform |
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
Pext |
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
Definitions
Field | Contents | SI Unit Example |
---|---|---|
mat_ID | Material
identifier. (Integer, maximum 10 digits) |
|
unit_ID | Unit Identifier. (Interger, maximum 10 digits) |
|
mat_title | Material
title. (Character, maximum 100 characters) |
|
Iform | Formulation
flag. (Integer) |
|
Pext | External pressure. 2 Default = 0 (Real) |
|
Kinematic viscosity shear
. 3 Default = 0 (Real) |
||
Kinematic viscosity
(volumetric),
which corresponds to Stokes
Hypothesis. 3 Default = 0 (Real) |
||
Initial volumetric
fraction. 4 (Real) |
||
Initial
density. (Real) |
||
Initial energy per unit
volume. (Real) |
||
Hydrodynamic cavitation
pressure. 5 If fluid material ( ), then default = . If solid material ( ), then default = -1e30. (Real) |
||
Initial
pressure. (Real) |
||
Hydrodynamic
coefficient. (Real) |
||
Hydrodynamic
coefficient. (Real) |
||
Hydrodynamic
coefficient. (Real) |
||
Hydrodynamic
coefficient. (Real) |
||
Hydrodynamic
coefficient. (Real) |
||
Elasticity shear modulus.
(Real) |
Example
/MAT/LAW51/1
99.99% Water + 0.01% Air-MULTIMAT: AIR+WATER,units{kg,m,s,Pa}
#(output is total pressure:Pext=0)
#--------------------------------------------------------------------------------------------------#
# Material Law No 51. MULTI-MATERIAL SOLID LIQUID GAS ALE-CFD-SPH
#--------------------------------------------------------------------------------------------------#
# Blank format
# IFORM
0
#---Global parameters------------------------------------------------------------------------------#
# P_EXT NU LAMDA
0 0 0
#---Material#1:AIR(PerfectGas)---------------------------------------------------------------------#
# ALPHA_1 RHO_0_1 E_0_1 P_MIN_1 C_0_1
0.0001 1.2 2.5E+05 0 0
# C_1_1 C_2_1 C_3_1 C_4_1 C_5_1
0 0 0 0.4 0.4
# G_1
0
#---Material#2:WATER(Linear_Incompressible)--------------------------------------------------------#
# ALPHA_2 RHO_0_2 E_0_2 P_MIN_2 C_0_2
0.9999 1000.0 0 0 0
# C_1_2 C_2_2 C_3_2 C_4_2 C_5_2
2.25E+9 0 0 0 0
# G_2
0
#---Material#3:not defined-------------------------------------------------------------------------#
# ALPHA_3 RHO_0_3 E_0_3 P_MIN_3 C_0_3
0.0 0 0 0 0
# C_1_3 C_2_3 C_3_3 C_4_3 C_5_3
0 0 0 0 0
# G_3
0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/LAW51/1
99.99% Water + 0.01% Air-MULTIMAT: AIR+WATER,units{kg,m,s,Pa}
#(output is relative pressure to Pext=1E+5Pa)
#--------------------------------------------------------------------------------------------------#
# Material Law No 51. MULTI-MATERIAL SOLID LIQUID GAS -ALE-CFD-SPH
#--------------------------------------------------------------------------------------------------#
# Blank format
# IFORM
0
#---Global parameters------------------------------------------------------------------------------#
# P_EXT NU LAMDA
1E+5 0 0
#---Material#1:AIR(PerfectGas)---------------------------------------------------------------------#
# ALPHA_1 RHO_0_1 E_0_1 P_MIN_1 C_0_1
0.0001 1.2 2.5E+05 0 -1E+5
# C_1_1 C_2_1 C_3_1 C_4_1 C_5_1
0 0 0 0.4 0.4
# G_1
0
#---Material#2:WATER(Linear_Incompressible)--------------------------------------------------------#
# ALPHA_2 RHO_0_2 E_0_2 P_MIN_2 C_0_2
0.9999 1000.0 0 0 0
# C_1_2 C_2_2 C_3_2 C_4_2 C_5_2
2.25E+9 0 0 0 0
# G_2
0
#---Material#3:not defined-------------------------------------------------------------------------#
# ALPHA_3 RHO_0_3 E_0_3 P_MIN_3 C_0_3
0.0 0 0 0 0
# C_1_3 C_2_3 C_3_3 C_4_3 C_5_3
0 0 0 0 0
# G_3
0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
Comments
- Numerical diffusion can be improved using the second order method for volume fraction convection, /ALE/MUSCL. The previous /UPWIND used to limit diffusion is now obsolete
-
Radioss computes and outputs a relative pressure
.
(6) However, total pressure is essential for energy integration ( ). It can be computed with the external pressure flag Pext.
leads to .
This means that if Pext = 0, the computed pressure is also the total pressure:
- Kinematic viscosities
are global and is not specific to each material. It allows computing viscous stress
tensor:
(7) Where,- Kinematic viscosity in shear
- Kinematic volumetric viscosity
- Volumetric fractions enable the sharing of elementary volume within the
three different materials.
For each material must be defined between 0 and 1.
Sum of initial volumetric fractions must be equal to 1.
For automatic initial fraction of the volume, refer to the /INIVOL card.
-
flag is the minimum value for the computed pressure
. It means that total pressure is also bounded
to:
(8) For fluid materials and detonation products, must remain positive to avoid any tensile strength so must be set to .
For solid materials, default value = 1e-30 is suitable but may be modified.
- Material tracking is possible through animation
files:
/ANIM/BRIC/VFRAC (All material volumetric fractions)