Block Format Keyword Describes the Murnaghan equation of state.
Format
(1) |
(2) |
(3) |
(4) |
(5) |
(6) |
(7) |
(8) |
(9) |
(10) |
/EOS/MURNAGHAN/mat_ID/unit_ID |
eos_title |
K0 |
K1 |
P0 |
Psh |
|
Definition
Field |
Contents |
SI Unit Example |
mat_ID |
Material identifier. (Integer, maximum
10 digits)
|
|
unit_ID |
Unit Identifier. (Integer, maximum 10 digits)
|
|
eos_title |
EOS title. (Character, maximum 100
characters)
|
|
K0 |
Material parameter. (Real)
|
|
K1 |
Material parameter. (Real)
|
|
P0 |
Initial pressure. (Real)
|
|
Psh |
Pressure shift. (Real)
|
|
Example
#---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/HYDPLA/7
Elastic Solid - Sodium Chloride (NaCl)
# RHO_I RHO_0
2.16e-3 0
# E nu
39980.0 0.26
# a b n eps_max sigma_max
1E20 0 0 0 0
# Pmin
0
/EOS/MURNAGHAN/7
Sodium Chloride (NaCl) at atmospheric pressure
# K0 K1 P0 PSH
24000 5.390 .1 0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
Comments
- This equation of state is also known as Tait
Equation of State.(1)
Where
and
are material parameters.
- This equation can also be found with
the following form:(2)
With,
and
- In some publications, the material
parameters
and
are replaced by
and
with,
and
.
- Another way to express this equation
is with the compressibility
.(3)
with
- Murnaghan EOS does not depend on
energy.
- Equations of state are used by
Radioss to compute the hydrodynamic pressure and are
compatible with the material laws:
- /MAT/LAW3 (HYDPLA)
- /MAT/LAW4 (HYD_JCOOK)
- /MAT/LAW6 (HYDRO or HYD_VISC)
- /MAT/LAW10 (DPRAG1)
- /MAT/LAW12 (3D_COMP)
- /MAT/LAW49 (STEINB)
- /MAT/LAW102 (DPRAG2)
- /MAT/LAW103 (HENSEL-SPITTEL)