Iform = 2
Block Format Keyword This boundary material enables to impose sub-material states (density, energy, and volumetric fraction) which are also used to compute global material state. Submaterial EOS parameters must be consistent with the ones in adjacent element (from the domain).
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
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/MAT/LAW51/mat_ID/unit_ID | |||||||||
mat_title | |||||||||
Blank Format | |||||||||
Iform |
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
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Scaletime | PEXT |
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
fct_IDα1 | fct_ID 1 | ||||||||
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
fct_IDα2 | fct_ID 2 | fct_IDE2 | |||||||
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
fct_IDα3 | fct_ID 3 | fct_IDE3 | |||||||
Definitions
Field | Contents | SI Unit Example |
---|---|---|
mat_ID | Material identifier (Integer, maximum 10 digits) |
|
unit_ID | Unit Identifier. (Interger, maximum 10 digits) |
|
mat_title | Material title (Character, maximum 100 characters) |
|
Iform | Formulation flag (Integer) =2 : Imposed state |
|
Scaletime | Abscissa scale factor for input
functions Default = 1 (Real) |
|
Scale factor for inlet velocity 5
(Real) |
||
fct_IDVEL | Optional identifier for velocity
function
5 = 0 : > 0 : (Integer) |
|
Initial imposed volumetric fraction
2 (Real) |
||
Initial imposed
density (Real) |
||
Initial imposed energy per unit
volume (Real) |
||
fct_IDαi | Optional identifier for Volumetric
fraction scaling function
3 = 0 : > 0 : (Integer) |
|
fct_ID | Optional identifier for Density fraction
scaling function
3 = 0 : > 0 : (Integer) |
|
fct_IDEi | Optional identifier for density energy
scaling function identifier
3 = 0: > 0 : (Integer) |
|
Coefficient for Polynomial
EOS (Real) |
||
Coefficient for Polynomial
EOS (Real) |
||
Coefficient for Polynomial
EOS (Real) |
||
Coefficient for Polynomial
EOS (Real) |
||
Coefficient for Polynomial
EOS (Real) |
||
Cut off pressure 4 Default = -10-30 (Real) |
||
Coefficient for Polynomial
EOS (Real) |
Comments
- This formulation imposes sub-material states from user data.Volumetric fraction:
(1) Density:(2) Density Energy:(3) This enables to compute pressure from given polynomial EOS:(4) Where, and , which means that EOS is linear in expansion and cubic for in compression.
Then global material state is determined by:- Pressure
- Density
- Energy
- Volumetric fractions enable the sharing of elementary volume within the three
different materials.
For each material must be defined between 0 and 1.
Sum of initial volumetric fractions must be equal to 1.
For automatic initial fraction of the volume, refer to /INIVOL.
- If a function is not defined, then related quantity remains constant and set to its initial value. However, input quantity can be defined as time dependent function using provided function identifiers. Abscissa functions can also be scaled using Fscalet parameter which leads to use , instead of .
-
flag is the minimum value for the computed pressure.
Since , defining implies and .
Fluid materials pressure must remain positive to avoid any tensile strength, then,
or .
For solid materials, default value for = 1030 is suitable.
- If the velocity is not defined, the user must define it using /IMPVEL with nodes. Otherwise normal velocity can be entered. The normal velocity is applied to the global material with the same velocity used for each submaterial. If only the state at the stagnation point is known, use /MAT/LAW51 with Iform=4,5 instead.