Ityp = 0

Block Format Keyword This law enables to model a gas inlet condition by providing data from stagnation point. Gas is supposed to be a perfect gas.


law11_ityp0
Figure 1.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
/MAT/LAW11/mat_ID/unit_ID or /MAT/BOUND/mat_ID/unit_ID
mat_title
ρ i stagnation ρ 0 stagnation            
Ityp   Psh FscaleT        
Ityp = 0 - Gas Inlet (from stagnation point data)
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
node_IDV   C1     Cd    
fct _ ID ρ                  
fct_IDp   P 0 stagnation            
Blank Format
Blank Format
fct_IDT fct_IDQ                

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)

 
ρ i stagnation Initial stagnation density. 3

(Real)

[ kg m 3 ]
ρ 0 stagnation Reference density used in E.O.S (equation of state).

Default ρ 0 stagnation = ρ i stagnation (Real)

[ kg m 3 ]
Ityp Boundary condition type. 1
= 0
Gas inlet (from stagnation point data)
= 1
Liquid inlet (from stagnation point data)
= 2
General inlet/outlet
= 3
Non-reflecting boundary

(Integer)

 
Psh Pressure shift. 2

(Real)

[ Pa ]
FscaleT Time scale factor. 3

(Real)

[ s ]
node_IDV Node identifier for velocity computation. 4
= 0
v in = min nod e ε face v n o d e n
> 0
v in = v node _ ID

(Integer)

 
γ Perfect gas constant.

(Real)

 
Cd Discharge coefficient. 5

(Real)

 
fct_ID ρ Function f ρ ( t ) identifier for stagnation density. 3
= 0
ρ stagnation ( t ) = ρ i stagnation
> 0
ρ stagnation ( t ) = ρ i stagnation f ρ ( t )

(Integer)

 
fct_IDp Function f P ( t ) identifier for stagnation pressure. 3
= 0
P stagnation ( t ) = P 0 stagnation
> 0
P stagnation ( t ) = P 0 stagnation f P ( t )

(Integer)

 
P 0 stagnation Initial stagnation pressure. 3

(Real)

[ Pa ]
fct_IDT Function f T ( t ) identifier for inlet temperature. 3 6
= 0
T = T adjacent
= n
T = T 0 f T ( t )

(Integer)

 
fct_IDQ Function f Q ( t ) identifier for inlet heat flux. 3 6
= 0
No imposed flux
= n
Q = f Q ( t )

(Integer)

 

Comments

  1. Provided gas state from stagnation point ( ρ stagnation , P stagnation ) is used to compute inlet gas state.
    A set of equations including Total Enthalpy formulation, Adiabatic Law and Equation of State allows for the complete definition of the inlet state:(1)
    ρ in = ρ stagnation [ 1 γ 1 2 γ ρ stagnation P stagnation ( 1 + C d ) v in 2 ] 1 γ 1 P in = P stagnation ( ρ in ρ stagnation ) γ ( ρ e ) in = P in γ 1
  2. The Psh parameter enables shifting the output pressure which also becomes P-Psh. If using Psh=P(t=0), the output pressure will be Δ P MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeiLdiaadc faaaa@37E5@ , with an initial value of 0.0.
  3. If no function is defined, then related quantity ( P stagnation , ρ stagnation , T , or Q ) remains constant and set to its initial value. However, all input quantities ( P stagnation , ρ stagnation , T , and Q ) can be defined as time dependent function using provided function identifiers. Abscissa functions can also be scaled using FscaleT parameter which leads to use f (Fscalet * t) instead of f(t).
  4. Inlet velocity v in is used in Bernoulli theory.
  5. Discharge coefficient accounts for entry loss and depends on shape orifice.

    mat_bound_sharpedge
    Figure 2.
  6. With thermal modeling, all thermal data ( T 0 , ρ 0 C P , ...) can be defined with /HEAT/MAT.
  7. It is not possible to use this boundary material law with multi-material ALE laws 37 (/MAT/LAW37 (BIPHAS)) and 51 (/MAT/LAW51 (MULTIMAT)).