/EBCS/VALVIN
Block Format Keyword Describes the elementary boundary condition to describe inlet valve (imposed density and pressure).
Format
(1) | (2) | (3) | (4) | (5) | (6) | (7) | (8) | (9) | (10) |
---|---|---|---|---|---|---|---|---|---|
/EBCS/VALVIN/ebcs_ID/unit_ID | |||||||||
ebcs_title | |||||||||
surf_ID | |||||||||
C | |||||||||
fct_IDpr | Fscalepr | ||||||||
fct_IDrho | Fscalerho | ||||||||
fct_IDen | Fscaleen | ||||||||
lc | r1 | r2 |
Definition
Field | Contents | SI Unit Example |
---|---|---|
ebcs_ID | Elementary boundary
condition identifier. (Integer, maximum 10 digits) |
|
unit_ID | Unit Identifier (Integer, maximum 10 digits) |
|
ebcs_title | Elementary boundary
condition title. (Character, maximum 100 characters) |
|
surf_ID | Surface
identifier. (Integer) |
|
C | Speed of sound. Default = 0 (Real) |
|
fct_IDpr | Function
identifier for pressure.
(Integer) |
|
Fscalepr | Pressure scale
factor. Default = 0 (Real) |
|
fct_IDrho | Function
identifier for density.
(Integer) |
|
Fscalerho | Density scale
factor. Default = 0 (Real) |
|
fct_IDen | Function
identifier for energy.
(Integer) |
|
Fscaleen | Energy scale
factor. Default = 0 (Real) |
|
Characteristic
length. Default = 0 (Real) |
||
r1 | Linear resistance. 5 Default = 0 (Real) |
|
r2 | Quadratic resistance.
5 Default = 0 (Real) |
Comments
- Input is general, no prior assumptions are enforced! Verify that the elementary boundaries are consistent with general assumptions of ALE (equation closure).
- It is not advised to use the Hydrodynamic Bi-material Liquid Gas Law (/MAT/LAW37 (BIPHAS)) with the elementary boundary conditions.
- Density, pressure, and energy are imposed according to a scale factor and a time function. If the function number is 0, the imposed density, pressure and energy are used.
- This keyword is less than four
or equal to six (non-reflective frontiers (NRF)) using:
(1) Pressure in the far field is imposed with a function of time. The transient pressure is derived from , the local velocity field V and the normal of the outlet facet.
Where, is the characteristic length, to compute cutoff frequency as:(2) - A resistance pressure is
computed and added to the current pressure.
(3) It aims at modeling the friction loss due to the valves.