/EOS/LINEAR
Block Format Keyword Describes the linear equation of state with initial pressure and bulk modulus.
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/EOS/LINEAR/mat_ID/unit_ID | |||||||||
eos_title | |||||||||
B | 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) |
|
Initial
pressure. (Real) |
||
B | Bulk
modulus. (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/LAW06/7/1
fluid material
# RHO_I
0.001
# NU PMIN
0 1e-20
/EOS/LINEAR/7/1
Water (linear approximation, Bulk = rho.c^2 = 0.001*1500*1500)
# P0 B PSH
0.1 2250.0 0.0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
Comments
- Linear EOS has the following
form:
Where,
which can be derived from a polynomial EOS:
Where, - Bulk modulus is usually
estimated as:
Where, is the initial sound speed.
- Psh parameter enables to shift output pressure. Output pressure will also be a relative pressure .
- Equations of state are used by Radioss to compute the hydrodynamic pressure and are compatible with the material laws: