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/MAT/LAW41 (LEE-TARVER)

/MAT/LAW41 (LEE-TARVER)

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/MAT/LAW41 (LEE-TARVER)

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/MAT/LAW41 - Lee-Tarver Material

Description

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

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/MAT/LAW41/mat_ID or /MAT/LEE-TARVER/mat_ID

mat_title

 

 

 

 

 

 

Ireac

 

 

 

 

 

 

 

 

 

Ar

Br

Ap

Bp

EQ

 

 

 

 

itr

 

E1

check

 

 

 

 

rki

ex

ri

 

 

 

 

rkg

yg

zg

ex1

 

 

k

X

tol

 

 

 

 

grow2

ex2

yg2

zg2

 

 

ccrit

fmxig

fmxgr

fmngr

 

 

G

Ti

 

 

 

 

 

 

hmtoggle_plus1Flag Definition

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)

= 1: for Lee-Tarver (default)

= 2: for Dyna

 

Ar

Reagents JWL parameter

(Real)

Br

Reagents JWL parameter

(Real)

Reagents JWL parameter

(Real)

 

Reagents JWL parameter

(Real)

 

Reagents JWL parameter (Comment 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)

 

E1

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) (Comment 5)

(Real)

 

fmngr

Coefficient (Dyna-2D) (Comment 5)

(Real)

 

G

Shear modulus

(Real)

Ti

Initial temperature (K)

(Real)

hmtoggle_plus1Example (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----|

hmtoggle_plus1Comments
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

mat_law41_Ireac1

Ireac = 2: “Ignition and growth” according to the formulation introduced in Dyna-2D

mat_law41_Ireac2

2.Coefficient grow1 is initialized by rkg
3.Coefficients yg1 and zg1 are respectively initialized by yg and zg.
4.Coefficients R3 and W1 are linked by the relation: R3 = W1Cv
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 symbol_v3:

Where, , R3 = W1Cv

In terms of symbol_u:

Where,

, and R3 = W1Cp

hmtoggle_plus1Reference

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

See Also:

Material Compatibility

Law Compatibility with Failure Model