/MAT/GAS

Block Format Keyword Describes the gas molecular weight and specific heat coefficients.

Format

Type is MASS
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/MAT/GAS/MASS/mat_ID/unit_ID
mat_title
MW                
Cpa Cpb Cpc Cpd Cpe
Cpf        
Type is MOLE
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/MAT/GAS/MOLE/mat_ID/unit_ID
mat_title
MW                
Cpa Cpb Cpc Cpd Cpe
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
CP CV            

Definitions

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)

 
Cpa Cpa coefficient in the relation Cp(T)

(Real)

[ J kg K ]
Cpb Cpb coefficient in the relation Cp(T)

(Real)

[ J kg K 2 ]
Cpc Cpc coefficient in the relation Cp(T)

(Real)

[ J kg K 3 ]
Cpd Cpd coefficient in the relation Cp(T)

(Real)

[ J kg K 4 ]
Cpe Cpe coefficient in the relation Cp(T)

(Real)

[ J K kg ]
Cpf Cpf coefficient in the relation Cp(T)

(Real)

[ J kg K 5 ]
CP Specific heat at constant pressure

(Real)

[ J kgK ]
CV Specific heat at constant volume

(Real)

[ 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

  1. If Type is MASS:(1)
    C p = ( C p a + C p b T + C p c T 2 + C p d T 3 + 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.

  2. If Type is MOLE:(2)
    C p = 1 M W ( C p a + C p b T + C p c T 2 + C p d T 3 + 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.

  3. If Type is CSTA, CP and CV are given per unit mass.
  4. 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
  5. Gas data is available on the NIST (National Institute of Standard and Technology) web site: http://webbook.nist.gov/chemistry/