/MAT/LAW41 (LEE_TARVER)

Block Format Keyword This material law describes detonation products using an ignition and growth model of a reactive material. The Lee-Tarver model is based on the assumption that ignition starts at local hot spots in the passage of shock front and grows outward from these sites. The reaction rate is controlled by the pressure and the surface area as in a deflagration process.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/MAT/LAW41/mat_ID or /MAT/LEE_TARVER/mat_ID
mat_title
ρ i ρ 0            
Ireac                  
Ar Br R 1 r R 2 r R 3 r
Ap Bp R 1 p R 2 p R 3 p
C ν r C ν p EQ        
itr   ε check        
rki ex ri        
rkg yg zg ex1    
k X tol        
grow2 ex2 yg2 zg2    
ccrit fmxig fmxgr fmngr    
G Ti            

Definitions

Field Contents SI Unit Example
mat_ID Material identifier

(Integer, maximum 10 digits)

 
mat_title Material title

(Character, maximum 100 characters)

 
ρ i Initial density

(Real)

[ kg m 3 ]
ρ 0 Reference density used in E.O.S (equation of state)

Default = ρ 0 = ρ i (Real)

[ kg m 3 ]
Ireac Ignition and growth model flag.
=1 (Default)
for Lee_Tarver
= 2
for Dyna

(Integer)

 
Ar Reagents JWL parameter

(Real)

[ Pa ]
Br Reagents JWL parameter

(Real)

[ Pa ]
R 1 r Reagents JWL parameter

(Real)

 
R 2 r Reagents JWL parameter

(Real)

 
R 3 r Reagents JWL parameter 4

(Real)

[ J m 3 K ]
AP Product JWL parameter

(Real)

[ Pa ]
BP Product JWL parameter

(Real)

[ Pa ]
R 1 p Product JWL parameter

(Real)

 
R 2 p Product JWL parameter

(Real)

 
R 3 p Product JWL parameter

(Real)

[ J m 3 K ]
C ν r Heat capacity reagents

(Real)

[ J m 3 K ]
C ν P Heat capacity product

(Real)

[ J m 3 K ]
EQ Heat reaction

(Real)

 
itr Maximum number of iterations for the mixing law

Default = 80 (Integer)

 
ε Precision on hydrodynamic balance

Default = 10-3 (Real)

 
check Limiter of the mass fraction of products

Default = 10-5 (Real)

 
rki Chemical kinetic coefficient of the starting phase (Lee-Tarver and Dyna-2D)

(Real)

 
ex Chemical kinetic coefficient of the starting phase (Lee-Tarver and Dyna-2D)

(Real)

 
ri Chemical kinetic coefficient of the starting phase (Lee-Tarver and Dyna-2D)

(Real)

 
rkg Chemical kinetic coefficient of the growing phase (Lee-Tarver and Dyna-2D)

(Real)

 
yg Chemical kinetic coefficient of the growing phase (Lee-Tarver and Dyna-2D)

(Real)

 
zg Chemical kinetic coefficient of the growing phase (Lee-Tarver and Dyna-2D)

(Real)

 
ex1 Chemical kinetic coefficient of the growing phase (Dyna-2D)

(Real)

 
k Numerical limiters coefficient (Lee-Tarver and Dyna-2D)

Default = 99.0 (Real)

 
X Numerical limiters coefficient (Dyna-2D)

Default = 99.0 (Real)

 
tol Numerical limiters coefficient (Dyna-2D)

Default = 0.0 (Real)

 
grow2 Growing phase 2 coefficient (Dyna-2D)

(Real)

 
ex2 Growing phase 2 coefficient (Dyna-2D)

(Real)

 
yg2 Growing phase 2 coefficient (Dyna-2D)

(Real)

 
zg2 Growing phase 2 coefficient (Dyna-2D)

(Real)

 
ccrit Starting threshold (for compression) (Dyna-2D)

(Real)

 
fmxig Starting threshold (mass fraction) (Dyna-2D)

(Real)

 
fmxgr Coefficient (Dyna-2D) 5

(Real)

 
fmngr Coefficient (Dyna-2D) 5

(Real)

 
G Shear modulus

(Real)

[ Pa ]
Ti Initial temperature (K)

(Real)

[ K ]

Example (LX17)

#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#-  2. MATERIALS:
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/LAW41/1
LX17 (unit Mg-mm-s)
#              RHO_I               RHO_0
                1900                   0
#    Ireac
         2
#                 Ar                  Br                 R1r                 R2r                 R3r
       4930000000000       -166000000000                7.44                3.72           3.3337E-5
#                 Ap                  Bp                 R1p                 R2p                 R3p
        696000000000          2500000000                 4.4                 .94              4.3E-6
#                Cvr                 Cvp                  Eq
                2781                1000                .088
#     iter                           EPS               check
         0                             0                   0
#                rki                  ex                  ri
           100000000                   1                   4
#                rkg                  yg                  zg                 ex1
          1000000000                .371                   3                .191
#                  K                   X                 tol
                   0                   0                   0
#              grow2                 ex2                 yg2                 zg2
                   0                   1                   1                   1
#              ccrit               fmxig               fmxgr               fmngr
                   0                 .25                   1                 100
#                  G                  Ti
            75000000                 298
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#ENDDATA
/END
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|

Reference

E.L. Lee and C.M. Tarver "Phenomenological model of shock initiation in heterogeneous explosives" Phy. Fluids Vol. 23, No. 12, December 1980.

Comments

  1. If f is the mass fraction of the products and p is the reduced pressure:
    Ireact = 1: "Ignition and growth" according to Lee/Tarver(1)
    df dt ) i = r ki * ( 1 f ) ex * ( ρ ρ 0 1 ) r i
    (2)
    df dt ) g = r kg * ( 1 f ) ex * f y g * f z g
    Ireac = 2: "Ignition and growth" according to the formulation introduced in Dyna-2D(3)
    df dt ) i = r ik * ( fmxig f ) ex * ( ρ ρ 0 1 ccrit ) r i
    (4)
    df dt ) g 1 = grow 1 * ( 1 f ) ex 1 * f y g 1 * P z g 1
    (5)
    df dt ) g 2 = grow 2 * ( 1 f ) ex 2 * f y g 2 * P z g 2
  2. Coefficient grow1 is initialized by rkg
  3. Coefficients yg1 and zg1 are respectively initialized by yg and zg.
  4. Coefficients R3 and ω are linked by the relation: R 3 = ω C ν
  5. Coefficients fmxgr and fmngr are the limiters of the growth rate according to the mass fraction of products.
  6. This material law is not compatible with ALE.
  7. Heat reaction energy EQ is supposed to be constant.
  8. Reagent pressure Pr and detonation products pressure Pr are computed using a modified Jones-Wilkins-Lee equation of state:
    In term of relative volume v :(6)
    P ( v , T ) = Ae R 1 v + Be R 2 v + R 3 T v

    Where, v = V V 0 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaamODaiabg2 da9maalaaabaGaamOvaaqaaiaadAfadaWgaaWcbaGaaGimaaqabaaa aaaa@3AA4@

    In terms of μ :(7)
    P ( μ , T ) = Ae R 1 / ( 1 + μ ) + Be R 2 / ( 1 + μ ) + R 3 T / ( 1 + μ )

    Where, μ = ρ ρ 0 1 = 1 v 1 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaeqiVd0Maey ypa0ZaaSaaaeaacqaHbpGCaeaacqaHbpGCdaWgaaWcbaGaaGimaaqa baaaaOGaeyOeI0IaaGymaiabg2da9maalaaabaGaaGymaaqaaiaadA haaaGaeyOeI0IaaGymaaaa@434F@ .