Iform = 12

Block Format Keyword Up to 4 different sub-materials (solid, liquid, gas and explosives) can be defined by specifying a material identifier and initial volume fraction.

The following materials can be defined as sub-materials:
  • LAW3 (HYDPLA)
  • LAW4 (HYD_JCOOK)
  • LAW5 (JWL)
  • LAW6 (HYDRO)
  • LAW10 (DPRAG1)
  • LAW102 (DPRAG2)
These materials can then reference the following equations of state:
  • /EOS/LINEAR
  • /EOS/POLYNOMIAL
  • /EOS/IDEAL-GAS
  • /EOS/STIFF-GAS

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/MAT/LAW51/mat_ID/unit_ID
mat_title
Blank
Iform                  
#Global Parameters
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
  ν          
Sub-material parameters (each sub-material one line, maximum 4 lines for 4 sub-materials)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
mat_ID1 α 0 m a t _ 1 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaeqySde2aa0baaSqaaiaaicdaaeaacaWGTbGaamyyaiaadshacaaM i8Uaai4xaiaaxcW7caaMb8UaaGjcVlaaigdaaaaaaa@46CF@              
Optional lines for up to 3 additional sub-material
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
mat_ID2 α 0 mat_2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaeqySde2aa0baaSqaaiaaicdaaeaacaWGTbGaamyyaiaadshacaaM i8Uaai4xaiaaxcW7caaMb8UaaGjcVlaaikdaaaaaaa@46D0@              
mat_ID3 α 0 m a t _ 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaeqySde2aa0baaSqaaiaaicdaaeaacaWGTbGaamyyaiaadshacaaM i8Uaai4xaiaaxcW7caaMb8UaaGjcVlaaikdaaaaaaa@46D0@              
mat_ID4 α 0 m a t _ 4 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaeqySde2aa0baaSqaaiaaicdaaeaacaWGTbGaamyyaiaadshacaaM i8Uaai4xaiaaxcW7caaMb8UaaGjcVlaaikdaaaaaaa@46D0@              

Definition

Field Contents SI Unit Example
mat_ID Material identifier.

(Integer, maximum 10 digits)

 
unit_ID Unit Identifier

(Integer, maximum 10 digits)

 
mat_title Material title.

(Character, maximum 100 characters)

 
Iform Formulation flag = 12.

(Integer)

 
ν Kinematic viscosity in shear ν = μ / ρ . 4

Default is computed from sub-material laws (Real)

[ m 2 s ]
mat_ID1 Material identifier for the 1st sub-material which must refer to LAW3, 4, 5, 6, 10, or 102.

Mandatory (Integer)

 
α 0 m a t _ 1 Initial volumetric fraction for the 1st sub-material.

Default = 0 (Real)

 
mat_IDi (Optional) Material Identifier from 2nd to 4th sub-material which must refer to LAW3, 4, 5, 6, 10 or 102.

Default = 0 (Integer)

 
α 0 m a t _ i (Optional) Initial volumetric fraction.

(Real)

 

Example (2 Submaterials)

Example for only two submaterials.
#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/1
unit for mat
                   g                  mm                  ms
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|				 
/MAT/LAW51/101/1
99.99% Water-MULTIMAT:AIR+WATER ,units {g,mm,ms}
#              RHO_I               RHO_0
             
#     IFLG
        12
#                                     NU               LAMDA
                                       0                   0
#    MAT_1             ALPHA_1
         5              0.9999
#    MAT_2             ALPHA_2
         4              0.0001   
/ALE/MAT/101/1
#     Modif. factor.
                   0	
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/HYDRO/4/1
AIR
#              RHO_I               RHO_0
             1.22e-6                   0 
#                Knu                Pmin
                   0                   0
/EOS/IDEAL-GAS/4/1
EoS for Air at atmospheric pressure
#              GAMMA                  P0                 PSH                  T0                RHO0
                 1.4                0.10                   0               300.0             1.22E-6  
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|				   
/MAT/LAW06/5/1
water
#              RHO_I        
               0.001          
#                KNU                PMIN
                   0                   0 
/EOS/STIFF-GAS/5/1
STIFF_GAS_WATER
#              GAMMA                  P0                 PSH              P_STAR                RHO0
                 6.1                0.10                   0              368.85  
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata

Comments

  1. The material law is based on a diffusive interface technique. Numerical diffusion can be improved using MUSCL method for volume fraction (/ALE/MUSCL). The previous /UPWIND method for limiting diffusion is now obsolete.
  2. The sub-materials can be listed in any order, but only one of them can be an explosive sub-material /MAT/LAW5.
  3. If 4 sub-materials are requested, at least one of them should be an explosive sub-material /MAT/LAW5.
  4. Kinematic viscosities are global and are not specific to each material. They are used to compute the viscous stress tensor:(1)
    τ = μ [ ( V ) + t ( V ) ] + λ ( V ) I MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaaCiXdiabg2da9iabeY7aTnaadmGabaWaaeWaceaacqGHhis0cqGH xkcXcaWHwbaacaGLOaGaayzkaaGaey4kaSIaaGPaVpaaCaaaleqaba GaamiDaaaakiaaygW7daqadiqaaiabgEGirlabgEPielaahAfaaiaa wIcacaGLPaaaaiaawUfacaGLDbaacqGHRaWkcqaH7oaBdaqadiqaai abgEGirlaahAfaaiaawIcacaGLPaaacaWHjbaaaa@5817@
    Where,
    ν = μ / ρ
    Kinematic viscosity in shear.
    μ
    Automatically computed from mixture sub-material definition (LAW6): µ= i=1 N submat α i µ i MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaamyTaiabg2da9maaqahabaGaeqySde2aaSbaaSqaaiaadMgaaeqa aOGaamyTamaaBaaaleaacaWGPbaabeaaaeaacaWGPbGaeyypa0JaaG ymaaqaaiaad6eadaWgaaadbaGaam4CaiaadwhacaWGIbGaamyBaiaa dggacaWG0baabeaaa0GaeyyeIuoaaaa@4C8D@
    If a value is input to define μ , it will be applied to whatever the multi-material mixture is.
    λ
    Calculated such as 3 λ + 2 μ = 0 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbwvMCKf MBHbqefqvATv2CG4uz3bIuV1wyUbqedmvETj2BSbqefm0B1jxALjhi ov2DaebbnrfifHhDYfgasaacH8WjY=viVeYth9vqqj=hEieu0xXdbb a9frFf0=yqFf0dbba91qpepeI8k8fiI+fsY=rqaqpepae9pg0Firpe pesP0xe9Fve9Fve9qapdbaGaaiGadiWaamaaceGaaqaacaqbaaGcba GaaG4maiabeU7aSjabgUcaRiaaikdacqaH8oqBcqGH9aqpcaaIWaaa aa@412B@ (Stokes hypothesis).
  5. Volumetric fractions enable the sharing of elementary volume within the three different materials.

    For each material α 0 m a t _ i must be defined between 0 and 1.

    Sum of initial volumetric fractions i = 1 3 α 0 m a t _ i must be equal to 1.

    For automatic initial fraction of the volume, refer to the /INIVOL card.

  6. It is not recommended to use this law with Radioss single precision engine.