Block Format Keyword Describes the ideal gas equation of state
.
Format
(1) |
(2) |
(3) |
(4) |
(5) |
(6) |
(7) |
(8) |
(9) |
(10) |
/EOS/IDEAL-GAS/mat_ID/unit_ID or /EOS/IDEAL-GAS-VE/mat_ID/unit_ID |
eos_title |
|
P0 |
Psh |
T0 |
|
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) |
|
|
Heat capacity ratio
. (Real) |
|
P0 |
Initial
pressure. (Real) |
|
Psh |
Pressure
shift. (Real) |
|
T0 |
Initial
temperature. (Real) |
|
Example (Air)
#---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/HYDRO/7/1
AIR
# RHO_I RHO_0
1.22e-6 0
# Knu Pmin
1.5E-2 0
/EOS/IDEAL-GAS/7/1
EoS for Air at atmospheric pressure
# GAMMA P0 PSH T0
1.4 0.10 0 300.0
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#enddata
Comments
- Ideal-gas thermal EOS is:
Where,
-
- Specific volume
-
- Specific gas constant
-
- Temperature
Previous form of
can be written in the
form.
Where,
with
Where,
and
are constant parameters.
Consequently,
the same equation of state can be built using
/EOS/IDEAL-GAS-VT (Volume Temperature) defining the
special case of a constant function:
- Some characteristics of this equation of state:
- Ideal Gas
-
-
-
-
- Sounce speed
-
-
-
- For this equation of state,
,
and
are constant parameters.
In other cases,
/EOS/IDEAL-GAS-VT (Volume Temperature) must be
used.
The heat capacity
is computed from the initial
data:
This parameter enables the calculation of the gas
temperature since
Where,
-
- Specific energy by mass
- Equations of state are used by
Radioss to compute the hydrodynamic pressure and are
compatible with the material laws: