/MAT/GAS

Format

Type is MASS

(1)	(3)	(5)	(7)	(9)
/MAT/GAS/`MASS`/`mat_ID`/`unit_ID`
`mat_title`
`MW`
`C`_pa	`C`_pb	`C`_pc	`C`_pd	`C`_pe
`C`_pf

Type is MOLE

(1)	(3)	(5)	(7)	(9)
/MAT/GAS/`MOLE`/`mat_ID`/`unit_ID`
`mat_title`
`MW`
`C`_pa	`C`_pb	`C`_pc	`C`_pd	`C`_pe

Type is PREDEF

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/MAT/GAS/`PREDEF`/`mat_ID`/`unit_ID`
`mat_title`
4

Type is CSTA

(1)	(2)	(3)	(4)	(5)	(6)	(7)	(8)	(9)	(10)
/MAT/GAS/`CSTA`/`mat_ID`/`unit_ID`
`mat_title`
`C`_P		`C`_V

Definition

Field	Contents	SI Unit Example
`mat_ID`	Material identifier (Integer, maximum 10 digits)
`unit_ID`	Unit Identifier (Integer, maximum 10 digits)
`mat_title`	Material title (Character, maximum 100 characters)
`MW`	Molecular weight of gas (Real > 0)
`C`_pa	`C`_pa coefficient in the relation `C`_p(T) (Real)	$[\frac{J}{kg \cdot K}]$
`C`_pb	`C`_pb coefficient in the relation `C`_p(T) (Real)	$[\frac{J}{kg \cdot K^{2}}]$
`C`_pc	`C`_pc coefficient in the relation `C`_p(T) (Real)	$[\frac{J}{kg \cdot K^{3}}]$
`C`_pd	`C`_pd coefficient in the relation `C`_p(T) (Real)	$[\frac{J}{kg \cdot K^{4}}]$
`C`_pe	`C`_pe coefficient in the relation `C`_p(T) (Real)	$[\frac{J \cdot K}{kg}]$
`C`_pf	`C`_pf coefficient in the relation `C`_p(T) (Real)	$[\frac{J}{kg \cdot K^{5}}]$
`C`_P	Specific heat at constant pressure (Real)	$[\frac{J}{k g K}]$
`C`_V	Specific heat at constant volume (Real)	$[\frac{J}{k g K}]$

Input Type Keyword

Keyword: Input Type
MASS: Coefficients of Cp(T) per mass unit
MOLE: Coefficients of Cp(T) per mole
PREDEF: Predefined gas name
CSTA: Cp constant with temperature

Example (Gas)

#RADIOSS STARTER
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/UNIT/1
unit for mat
                  kg                  mm                  ms
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
/MAT/GAS/CSTA/5/1
Nitrogen
#                 cp                  cv
               931.5               634.7
#---1----|----2----|----3----|----4----|----5----|----6----|----7----|----8----|----9----|---10----|
#ENDDATA
/END

Comments

If Type is MASS:(1)
$C_{p} = (C_{p a} + C_{p b} T + C_{p c} T^{2} + C_{p d} T^{3} + \frac{C_{p e}}{T^{2}} + C_{p f} T^{4})$

Where, $C_{p a}$ is the energy per mass unit per Kelvin and $C_{p b}$ is the energy per mass unit per Kelvin.
If Type is MOLE:(2)
$C_{p} = \frac{1}{M W} (C_{p a} + C_{p b} T + C_{p c} T^{2} + C_{p d} T^{3} + \frac{C_{p e}}{T^{2}})$

Where, $M W$ is the molecular weight, mass per mole; $C_{p a}$ is the energy per mole per Kelvin, and $C_{p b}$ is the energy per mole per Kelvin.
If Type is CSTA, C_P and C_V are given per unit mass.
The units in the database are automatically translated to the global unit system.
Listed below are names of 14 commonly used gases predefined in Radioss: N2, O2, Air, etc. These will be referred to by a gas material identifier, while defining INJECTOR.

Predefined Gas Name

Gas

N2

Nitrogen

O2

Oxygen

CO2

Carbon dioxide

CO

Carbon monoxide

AR

Argon

NE

Neo

HE

Helium

H2

Hydrogen

H2O

Water vapor

NH3

Ammonia

N2S

Hydrogen sulfide

C6H6

Benzene

N2O

Nitrous oxide

AIR

Air
Gas data is available on the NIST (National Institute of Standard and Technology) web site: http://webbook.nist.gov/chemistry/