/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 | |||||||||
Ireac | |||||||||
Ar | Br | ||||||||
Ap | Bp | ||||||||
EQ | |||||||||
itr | 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) |
|
Initial density (Real) |
||
Reference density used in E.O.S (equation of
state) Default = (Real) |
||
Ireac | Ignition and growth model flag.
(Integer) |
|
Ar | Reagents JWL parameter (Real) |
|
Br | Reagents JWL parameter (Real) |
|
Reagents JWL parameter (Real) |
||
Reagents JWL parameter (Real) |
||
Reagents JWL parameter 4 (Real) |
||
AP | Product JWL parameter (Real) |
|
BP | Product JWL parameter (Real) |
|
Product JWL parameter (Real) |
||
Product JWL parameter (Real) |
||
Product JWL parameter (Real) |
||
Heat
capacity reagents (Real) |
||
Heat
capacity product (Real) |
||
EQ | Heat
reaction (Real) |
|
itr | Maximum number of iterations for the mixing
law Default = 80 (Integer) |
|
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) |
|
Ti | Initial temperature (K) (Real) |
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
- 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) (2) Ireac = 2: "Ignition and growth" according to the formulation introduced in Dyna-2D(3) (4) (5) - Coefficient grow1 is initialized by rkg
- Coefficients yg1 and zg1 are respectively initialized by yg and zg.
- Coefficients R3 and are linked by the relation:
- Coefficients fmxgr and fmngr are the limiters of the growth rate according to the mass fraction of products.
- This material law is not compatible with ALE.
- Heat reaction energy EQ is supposed to be constant.
- Reagent
pressure Pr and detonation products
pressure Pr are computed using a modified
Jones-Wilkins-Lee equation of state:In term of relative volume :
(6) Where,
In terms of :(7) Where, .